解出来了,非常开心,望采纳。
解:
因为:
x²+3x=6
则:
x(x²+3x)=6x
x³+3x²=6x
x³+3x²-6x=0
x³+x²-12x+10
=x³+3x²-2x²-6x-6x+10
=(x³+3x²-6x)-2x²-6x+10
=-2x²-6x+10
=-2(x²+3x)+10
=-2×6+10
=-2
解:
x²+3x=6
x²=-3x+6
x³=x*x²=x(-3x+6)=-3x²+6x
于是
x³+x²-12x+10
=-3x²+6x+x²-12x+10
=-2x²-6x+10
=-2(x²+3x)+10
=-2*6+10
=-2