(x-2)(x-a-3)求展开 要每一步详细步骤

问题描述:

(x-2)(x-a-3)求展开 要每一步详细步骤

(x-2)(x-a-3)
=(x-2)(x-a)-3(x-2)
=(x-2)x-(x-2)a-3(x-2)
=x^2-2x-ax+2a-3x+6
=x^2-5x-ax+2a+6或者x^2-(5+a)x+2a+6