Question

Answer 1

Bài 1 đây nhá

Answer 2

Bài 2: 

a) Ta có: \(A\left(x\right)=-5x+4x^3-8x^2+8\)

\(=4x^3-8x^2-5x+8\)

Ta có: \(B\left(x\right)=-4x^3+7x-10+8x^2\)

\(=-4x^3+8x^2+7x-10\)

b) Ta có: A(x)+B(x)

\(=4x^3-8x^2-5x+8-4x^3+8x^2+7x-10\)

\(=2x-2\)

Ta có: A(x)-B(x)

\(=4x^3-8x^2-5x+8+4x^3-8x^2-7x+10\)

\(=8x^3-16x^2-12x+18\)

c) Đặt A(x)+B(x)=0

\(\Leftrightarrow2x-2=0\)

\(\Leftrightarrow2x=2\)

hay x=1