Đáp án + Giải thích các bước giải:
a)
`h(x)=f(x)-g(x)`
`=>h(x)=(x^5+2x^4-x^2-1)-(3x^5-x^4-3x^3+2x-6)`
`=>h(x)=x^5+2x^4-x^2-1-3x^5+x^4+3x^3-2x+6`
`=>h(x)=(x^5-3x^5)+(2x^4+x^4)-x^2-(1-6)+3x^3+2x`
`=>h(x)=-2x^5+3x^4-x^2+5+3x^3+2x`
`h(-1)=-2.(-1)^5+3.(-1)^4-(-1)^2+5+3.(-1)^3+2.(-1)`
`=>h(-1)=-2.(-1)+3.1-1+5+3.(-1)-2`
`=>h(-1)=2+3-1+5-3-2`
`=>h(-1)=4`
b)
`q(x)=g(x)-f(x)`
`=>q(x)=(3x^5-x^4-3x^3+2x-6)-(x^5+2x^4-x^2-1)`
`=>q(x)=3x^5-x^4-3x^3+2x-6-x^5-2x^4+x^2+1`
`=>q(x)=(3x^5-x^5)-(x^4+2x^4)-3x^3+2x-(6-1)+x^2`
`=>q(x)=2x^5-3x^4-3x^3+2x-5+x^2`
`q(-2)=2.(-2)^5-3.(-2)^4-3.(-2)^3+2.(-2)-5+(-2)^2`
`=>q(-2)=2.(-32)-3.16-3.(-8)-4-5+4`
`=>q(-2)=-64-48+24-4-5+4`
`=>q(-2)=-93`
