分式运算(1/a+3)-(6/9-a^)

问题描述:

分式运算(1/a+3)-(6/9-a^)

(1/a+3)-(6/9-a^2)
=(1/a+3)+(6/a^2-9)
=(a-3+6)/(a^2-9)
=(a-3)/(a-3)(a+3)
=1/(a+3)