(a平方除以a-2-4除以a-2)乘1除以a平方+2a
问题描述:
(a平方除以a-2-4除以a-2)乘1除以a平方+2a
答
[a平方/(a-2) - 4/(a-2)]×1/(a平方+2a)
= (a平方-4)/(a-2) × 1/a(a+2)
= (a+2)(a-2)/(a-2)× 1/a(a+2)
=1/a