Question

giúp em làm bài với ạ

Answer 1

a: =2x^4-8x^2+10x+x^3-4x+5

=2x^4+x^3-8x^2+6x+5

b: =\(\left(-x^3-\dfrac{1}{2}x\right)\left(2x^3+x^2-1\right)\)

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

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

c: \(=-5x^4-4x^3+5x^2+25x^3+20x^2-25x\)

\(=-5x^4+21x^3+25x^2-25x\)

d: \(=\left(3x^2+9x+3\right)\left(2x-x^2\right)\)

\(=6x^3-3x^4+18x^2-9x^3+6x-3x^2\)

\(=-3x^4-3x^3+15x^2+6x\)