二次根式的加减:(2√x-3√y)²-(3√x-2√y)²
问题描述:
二次根式的加减:(2√x-3√y)²-(3√x-2√y)²
答
=[(2√x-3√y)+(3√x-2√y)][(2√x-3√y)-(3√x-2√y)]
=(5√x-5√y)(-√x-√y)
=-5(√x-√y)(√x+√y)
=5y-5x