Сократите дробь: b^12+b^6+1/b^18-1
B⁶=x b¹²=(b⁶)²=x² b¹⁸=(b⁶)³=x³ (x²+x+1)/(x³-1)=(x²+x+1)/((x-1)(x²+x+1))=1/(x-1)=1/(b⁶-1)