Question

cho 2 đa thức :p(x)= 5x^5 +3x-4x^4 -2x^3+6+4x^2

                    Q(x)=2X^{4 _{- X+3X}2 _-} 2x³ +1/4 -X²

^{TÍNH A=P(x)+ Q(x) VÀ P(x) -Q(x)}

Answer 1

A= P(x) + Q(x)  \(=5x^5+3x-4x^4-2x^3+6+4x^2+2x^4-x+3x^2-2x^3+\dfrac{1}{4}-x^2\)

\(=5x^5\left(3x-x\right)-\left(4x^4+2x^4\right)-\left(2x^3-2x^3\right)+\left(4x^2+3x^2-x^2\right)+\left(6+\dfrac{1}{4}\right)\)

\(=5x^5+2x-6x^4+6x^2+\dfrac{25}{4}\)

 

A = P(x) - Q(x)

\(=5x^5+3x-4x^4-2x^3+6+4x^2-2x^4+x-3x^2+2x^3-\dfrac{1}{4}+x^2\)

\(=5x^5+\left(3x+x\right)-\left(4x^4-2x^4\right)-\left(2x^3-2x^3\right)+\left(4x^2-3x^2+x^2\right)+\left(6-\dfrac{1}{4}\right)\)

\(=5x^5+4x-2x^4+2x^2+\dfrac{23}{4}\)