từng câu 1 thoi nha bạn (nhiều qué ko có ng làm đou)
Câu 5
a)\(H\left(x\right)+R\left(x\right)=4x^3-2x^2+x-5+x^3-4x^2-3x+2\)
\(H\left(x\right)+R\left(x\right)=\left(4x^3+x^3\right)+\left(-2x^2-4x^2+\right)x-3x+\left(-5+2\right)\)
\(H\left(x\right)+R\left(x\right)=5x^3-6x^2-2x-3\)
b)\(H\left(x\right)-R\left(x\right)=4x^3-2x^2+x-5-x^3+4x^2+3x-2\)
\(H\left(x\right)+R\left(x\right)=\left(4x^3-x^3\right)+\left(4x^2-2x^2\right)+\left(x+3x\right)+\left(-5-2\right)\)
\(H\left(x\right)-R\left(x\right)=3x^3+2x^2+4x-7\)
Câu 7 cho P(x) = 0
=>`3x-5=0`
`=>3x=5``=>x=5/3`
Cho Q(x) = 0
`=>6-2x=0`
`=>2x=6``=>x=6/2 = 3`
Cho M(y)= 0
=>`1/2 y -3 =0`
`=>1/2 y =3 ` `=>y=6`