化简求值(3x+2)(3x-2)-5x(x-1)-(x-1)^2,其中x^2-x-2012=0
x^2-x-2012=0
x²-x=2012
(3x+2)(3x-2)-5x(x+1)-(x-1)^2 5x(x-1)换成5x(x+1)
=9x²前帆-4-5x²-5x-x²顷燃+2x-1
=3x²-3x-1
=3(x²雀悔虚-x)-1
=6036-1
=6035
(3x+2)(3x-2)-5x(x-1)-(x-1)²
=9x²-4-5x²慧悔稿+5x-x²前孝+2x-1
=3x²+7x-5
∵x²-x-2012=0
原式=3(x²-x-2012)+4x-4x+6031=4(x²前逗-x-2012)+6031+8048=14079
