Question

Cho 2 đa thức :

P(x)= \(^{x^3}\)-2x+1

Q(x)=\(^{2x^2}\)-\(^{2x^3}\)+x-5

Tính P(x)+Q(x)

P(x)-Q(x)

Answer 1

Chờ mình chút

Answer 2

Chọn mình nhé   

\(P\left(x\right)=x^3-2x+1\)

\(Q\left(x\right)=2x^2-2x^3+x-5\)

ta có:

\(P\left(x\right)+Q\left(x\right)=\left(x^3-2x+1\right)+\left(2x^2-2x^3+x-5\right)\)

\(P\left(x\right)+Q\left(x\right)=x^3-2x+1+2x^2-2x^3+x-5\)

\(P\left(x\right)+Q\left(x\right)=\left(x^3-2x^3\right)+2x^2-\left(2x-x\right)+\left(1-5\right)\)

\(P\left(x\right)+Q\left(x\right)=-x^3+2x^2-x-4\)

ta lại có:

\(P\left(x\right)-Q\left(x\right)=\left(x^3-2x+1\right)-\left(2x^2-2x^3+x-5\right)\)

\(P\left(x\right)-Q\left(x\right)=x^3-2x+1-2x^2+2x^3-x+5\)

\(P\left(x\right)-Q\left(x\right)=\left(x^3+2x^3\right)-2x^2-\left(2x+x\right)+\left(1+5\right)\)

\(P\left(x\right)+Q\left(x\right)=3x^3-2x^2-3x+6\)