A
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B
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C
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A&B
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⌐ (A&B)
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A\/B
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A\/B~C
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α(A, B, C)= ⌐(A&B)→(A\/B~C)
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0
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0
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0
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0
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1
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0
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1
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1
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0
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0
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1
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0
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1
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0
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0
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0
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0
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1
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0
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0
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1
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1
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0
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0
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0
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1
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1
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0
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1
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1
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1
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1
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1
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0
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0
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0
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1
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1
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0
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0
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1
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0
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1
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0
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1
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1
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1
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1
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1
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1
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0
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1
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0
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1
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0
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1
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1
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1
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1
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1
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0
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1
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1
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1
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Quyidagi mantiq algebrasi funksiyalari uchun rostlik jadvallarini tuzing;
F(A,B,C)= AB(AC)
F(A,B,C)=C→(AB)
F(A,B,C)=A&B→(AB)
F(A,B,C)=(A&B&C)(A B)
F(A,B,C)=(AC)B
F(A,B,C)=(A→B)→C
F(A,B,C)=(A→B)(B→C)
F(A,B,C)=A(B→C)B
F(A,B,C)=(A&BC)
F(A,B,C)=(AB)(BC)
F(A,B,C)=(A→C)B
F(A,B,C)=(BC)→(AC)
F(A,B,C)=A→(BC)
F(A,B,C)=(A→B)(B→A)C
F(A,B,C)=CAB
F(A,B,C)=A(ABC)(AC)
F(A,B,C)=(AB)(BAC)
F(A,B,C)=A(BA)(AC)
F(A,B,C)=(A→B)&A&C
F(A,B,C)=(A&B)→(C&A)
F(A,B,C)=(A&BC)&A&C
F(A,B,C)=(A&BA&B)&(C→B)
F(A,B,C)=(AB CABC)AB
F(A,B,C)=(A→B)&(C→A)
F(A,B,C)=(AB&CA&C)&B
F(A,B,C)=(ABC)→AC
F(A,B,C)=(AB)→(CBA)
F(A,B,C)=(A→B)(CA)
F(A,B,C)=(AB)(CB)
F(A,B,C)=((AB)C)→A((BC)(AC)
1.5. Rostlik jadvali bo‘yicha mantiq funksiyasi ko‘rinishini tiklash
A
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B
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C
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α=α(A,B,C)
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0
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0
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0
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0
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0
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0
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1
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1
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0
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1
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0
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0
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0
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1
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1
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0
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1
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0
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0
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0
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1
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0
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1
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1
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1
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1
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0
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0
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1
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1
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1
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1
| Ushbu masala yechimini aniq misolda ko‘rib chiqamiz. Aytaylik A, B, C o‘zgaruvchilarga bog‘liq bo‘lgan α=α(A,B,C) formula berilgan bo‘lsin. Tushunarliki ush
bu rostlik jadvaliga ega bo‘lgan cheksiz ko‘p teng kuchli formulalar mavjud. Ulardan ikkitasini topishni ko‘rib chiqamiz.
Rostlik jadvalida α=α(A,B,C) formula 1 ga teng bo‘lgan qator nomerlarini yozib chiqamiz.
2-qator
6-qator
8-qator
Har bir qator mantiqiy imkoniyatlaridagina 1 ga teng bo‘lgan, boshqa imkoniyatlarda esa 0 ga teng bo‘lgan formulalarni yozib chiqamiz. Buning uchun 1 ga teng bo‘lgan qatordagi fikr o‘zgaruvchilari qiymatlarini 1(rost) ga aylantirib, fikr o‘zgaruvchilari kon’yunksiyasini olish lozim.
2-qator uchun: ⌐A&⌐B&C; 6-qator uchun: A&⌐B&C; 8-qator uchun: A&B&C bo‘ladi. Agar qatorlar bo‘yicha olingan formulalar diz’yunksiyasi olinsa hosil bo‘lgan formula qidirilayotgan formula bo‘ladi:
α=α(A,B,C)= ⌐A&⌐B&C\/ A&⌐B&C\/A&B&C (1)
Rostlik jadvalida α=α(A,B,C) formula 0 ga teng bo‘lgan qator nomerlarini yozib chiqamiz.
1-qator
3-qator
4-qator
5-qator
7-qator
Har bir qator mantiqiy imkoniyatlaridagina 0 ga teng bo‘lgan, boshqa imkoniyatlarda esa 1 ga teng bo‘lgan formulalarni yozib chiqamiz. Buning uchun 0 ga teng bo‘lgan qatordagi fikr o‘zgaruvchilari qiymatlarini 0(yolg‘on) ga aylantirib, fikr o‘zgaruvchilari diz’yumksiyasini olish lozim.
Shunda 1-qator uchun: A\/B\/C; 3-qator uchun: A\/B\/ ⌐C; 4-qator uchun: A\/⌐B\/⌐C; 5-qator uchun: ⌐A\/B\/C; 7-qator uchun: ⌐A\/⌐B\/C bo‘ladi.
Agar qatorlar bo‘yicha olingan formulalar kon’yunksiyasi olinsa, hosil bo‘lgan formula qidirilayotgan formula bo‘ladi.
α=α(A,B,C)=( A\/B\/C)&( A\/B\/ ⌐C)&( A\/⌐B\/⌐C)&( ⌐A\/B\/C)&( ⌐A\/⌐B\/C) (2)
(1) va (2) formulalar teng kuchli, chunki ularning rostlik jadvallari bir xil bo‘ladi. Shuning uchun ham ulardan qaysi birini tuzish kamroq ish talab qilsa shunisini tuzganimiz ma‘qul. Yuqoridagi misol ixtiyoriy umumiy hol uchun o‘rinli, ya’ni ixtiyoriy rostlik jadvali bo‘yicha formula ko‘rinishini shu prinsipda qurish mumkin.
Quyida rostlik jadvali bilan berilgan formulalarning MDNSh (mukammal diz’yunktiv normal shakl) va MKNSh (mukammal kon’yunktiv normal shakl) lari topilsin.
A
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B
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C
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F1
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F2
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F3
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F4
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F5
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F6
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F7
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F8
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F9
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F10
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F11
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F12
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F13
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F14
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F15
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0
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0
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0
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1
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1
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1
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0
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0
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1
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1
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0
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0
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0
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1
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0
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0
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0
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0
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0
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0
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1
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1
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0
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0
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1
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0
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1
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1
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1
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1
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1
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1
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1
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1
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1
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0
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0
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1
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0
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0
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1
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0
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0
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1
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1
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0
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1
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0
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0
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0
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1
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1
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1
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1
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0
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1
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1
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0
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0
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1
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1
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1
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0
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0
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0
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1
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0
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0
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0
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1
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1
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1
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1
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0
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0
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0
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0
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1
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1
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1
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0
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0
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1
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0
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1
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1
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0
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0
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0
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1
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1
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0
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1
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0
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1
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0
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0
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1
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0
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1
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0
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0
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1
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1
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1
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0
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0
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0
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1
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1
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0
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1
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0
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0
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1
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0
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0
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0
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1
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1
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1
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0
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1
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0
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1
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0
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1
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1
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1
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1
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1
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1
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0
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0
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1
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1
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0
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1
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0
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0
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0
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1
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0
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1
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A
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B
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C
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F16
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F17
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F18
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F19
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F20
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F21
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F22
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F23
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F24
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F25
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F26
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F27
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F28
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F29
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F30
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0
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0
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0
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0
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1
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0
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0
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0
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0
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0
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0
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0
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0
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1
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0
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1
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1
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1
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0
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0
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1
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0
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0
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1
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0
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0
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0
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0
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1
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0
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1
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0
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1
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1
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1
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0
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0
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1
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0
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1
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1
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0
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1
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0
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1
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0
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1
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1
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1
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1
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0
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0
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1
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1
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0
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1
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1
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1
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0
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1
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0
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1
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0
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1
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0
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1
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0
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1
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1
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1
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0
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1
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1
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