已知a=5,求(a-4)/(a²-9)÷1/(a-3)*(a²+6a+9)/(a²-8a+16)

问题描述:

已知a=5,求(a-4)/(a&sup2-9)÷1/(a-3)*(a&sup2+6a+9)/(a&sup2-8a+16)

(a-4)/(a²-9)÷1/(a-3)*(a²+6a+9)/(a²-8a+16)
=(a-4)/[(a+3)(a-3)]×(a-3)×(a+3)²/(a-4)²
=(a+3)/(a-4)
=8