Question

(b^2-49)*(b+1/b-7-b-1/b+7)-15*b+7
Упростите выражение

Answer 1

$(b^{2}-49)*(\frac{b+1}{b-7} -\frac{b-1}{b+7} )-15b+7=(b-7)(b+7)*(\frac{(b+1)(b+7)}{(b-7)(b+7)} -\frac{(b-1)(b-7)}{(b-7)(b+7)}) -15b+7=(b-7)(b+7)*(\frac{b^{2}+8b+7}{(b-7)(b+7)} -\frac{b^{2}-8b+7}{(b-7)(b+7)})-15b+7=(b-7)(b+7)*\frac{b^{2}+8b+7-b^{2}+8b-7}{(b-7)(b+7)} -15b+7=16b-15b+7=b+7$