Question

Answer 1

Câu 3 : 

a, Ta có : \(K\left(x\right)-L\left(x\right)+M\left(x\right)\)

\(=2x^2+3x-5-x^2-x+1-4x^2+2x-3=-x^2+4x-7\)

b, Ta có : \(K\left(x\right)-L\left(x\right)-2M\left(x\right)\)

\(=x^2+2x-4+8x^2-4x+6=9x^2-2x+2\)

Answer 2

Câu 2: 

\(Q\left(x\right)=2x^4-3x^3+5x^2+3x+1-2x^4+2x^3+x-1\)

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