几个高次方程 x^3-9x+8=0 (x+2)(x+3)(x+4)(x+5)=360 (x^-x)^2+4(3x^2-3x-7)=0

x^3-9x+8=0 x^3-8x-x+8=0(x-8)(x^2-1)=0x=2,1,-1(x+2)(x+3)(x+4)(x+5)=360 (x^2+7x+10)(x^2+7x+12)-360=0(x^2+7x)^2+22(x^2+7x)-240=0(x^2+7x-8)(x^2+7x+30)=0(x+8)(x-1)(x^2+7x+30)=0实根为x=1,8(x^-x)^2+4(3x^2-3x...