问题
解答题
已知f(x)=x2-x-2,g(x)=x2-6x+8,p(x)=x2+3x+2,计算[f(x)-g(x)]•p(x).
答案
由题意得:[f(x)-g(x)]•p(x)
=[(x2-x-2)-(x2-6x+8)]•(x2+3x+2)
=(5x-10)(x2+3x+2)
=5x3+15x2+10x-10x2-30x-20
=5x3+5x2-20x-20.
已知f(x)=x2-x-2,g(x)=x2-6x+8,p(x)=x2+3x+2,计算[f(x)-g(x)]•p(x).
由题意得:[f(x)-g(x)]•p(x)
=[(x2-x-2)-(x2-6x+8)]•(x2+3x+2)
=(5x-10)(x2+3x+2)
=5x3+15x2+10x-10x2-30x-20
=5x3+5x2-20x-20.