解方程 (3x+1)(3x-1)=(x+2)(9x-4) 2（x-3)(x-2)-(x+3)²=(x-1)(x+1)_数学解答

解方程 (3x+1)(3x-1)=(x+2)(9x-4) 2（x-3)(x-2)-(x+3)²=(x-1)(x+1)

人气：331 ℃　时间：2020-04-12 09:22:40

解答

(3x+1)(3x-1)=(x+2)(9x-4) 9x^2-1 = 9x^2+14x-8-14x=-7x=1/22(x-3)(x-2)-(x+3)²=(x-1)(x+1)2(x^2-5x+6)-(x^2+6x+9)=x^2-12x^2-10x+12-x^2-6x-9=x^2-1x^2-16x+3=x^2-1-16x=-4x=1/4