Question

Answer 1

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

\(B\left(x\right)=6x^3-2x^2+5x\)

a) \(A\left(x\right)+B\left(x\right)=3x^4-3x^3-2x+1+6x^3-2x^2+5x\)

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

b) \(2A\left(x\right)-3B\left(x\right)=2\left(3x^4-3x^3-2x+1\right)-3\left(6x^3-2x^2+5x\right)\)

\(=6x^4-6x^3-4x+2-18x^3+6x^2-15x\)

\(=6x^4-24x^3+6x^2-19x+2\)

Answer 2

Câu 1:

\(a,A\left(x\right)+B\left(x\right)=3x^4-3x^3-2x+1+6x^3-2x^2+6x=3x^4+3x^3-2x^2+4x+1\\ b,2A\left(x\right)-3B\left(x\right)=2\left(3x^4-3x^3-2x+1\right)-3\left(6x^3-2x^2+6x\right)=6x^4-6x^3-4x+2-18x^3+6x^2-18x=6x^4-24x^3+6x^2-22x+2\)

Answer 3

Câu 1 : 

a, \(A\left(x\right)+B\left(x\right)=3x^4-3x^3-2x+1+6x^3-2x^2+5x=3x^4+3x^3-2x^2+3x+1\)

b, \(2A\left(x\right)-3B\left(x\right)=6x^4-6x^3-4x+2-18x^3+6x^2-15x=6x^4-24x^3+6x^2-19x+2\)

Answer 4

Câu 2:
\(f\left(x\right)+g\left(x\right)=x^5-2x^4+x^2+1+3x^5-x^4+2x-4\\ =4x^5-3x^4+x^2+2x-3\\ =4.1^5-3.1^4+1^2+2.1-3\\ =4-3+1+2-3\\ =1\)

Answer 5

Câu 3:
\(f\left(x\right)-g\left(x\right)+h\left(x\right)\\ =x^3-2x^2+3x+1-x^3-x+1+2x^2-1\\ =2x+1\)

Answer 6

Câu 1:

\(A\left(x\right)+B\left(x\right)=3x^4-3x^3-2x+1+6x^3-2x^2+5x.\\ =3x^4+3x^3-2x^2+3x+1.\)

\(2A\left(x\right)-3B\left(x\right)=2\left(3x^4-3x^3-2x+1\right)-3\left(6x^3-2x^2+5x\right).\\ =6x^4-6x^3-4x+2-18x^3+6x^2-15x.\\ =6x^4-24x^3+6x^2-19x+2.\)

Câu 2:

\(f\left(1\right)+g\left(1\right)=1^5-2.1^4+1^2+1+3.1^5-1^4+2.1-4.\\ =1-2+1+1+3-1+2-4.\\ =1.\)