先化简,再求值x²-4分之2x+2-x分之1
问题描述:
先化简,再求值x²-4分之2x+2-x分之1
答
x²-4分之2x+2-x分之1
=2x/(x+2)(x-2)-(x+2)/(x+2)(x-2)
=(x-2)/(x+2)(x-2)
=1/(x+2)