先化简,再求值:(2x-1)2+(x+3)(x-3)-4x(x-1),其中x=-2

先化简,再求值:(2x-1)2+(x+3)(x-3)-4x(x-1),其中x=-2.
2024-12-04 03:42:28
推荐回答(1个)
回答(1):

(2x-1)2+(x+3)(x-3)-4x(x-1),
=4x2-4x+1+x2-9-4x2+4x,
=x2-8,
当x=-2时,原式=x2-8=(-2)2-8=4-8=-4.