Question

Cho đa thức:

A(x) = x^3 + 4x^2 - 2x +3

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

a. Tính A(x) - B(x)

b,Tính A(x) + B(x)

Answer 1

a)\(A\left(x\right)-B\left(x\right)=\left(x^3+4x^2-2x+3\right)-\left(x^3+4x^2-7x+5\right)\\ A\left(x\right)-B\left(x\right)=5x-2\)

b)\(A\left(x\right)+B\left(x\right)=\left(x^3+4x^2-2x+3\right)+\left(x^3+4x^2-7x+5\right)\\ A\left(x\right)+B\left(x\right)=2x^3+8x^2-9x+8\)

Answer 2

a) A(x) - B(x) = (x³ + 4x² - 2x + 3) - (x³ + 4x² - 7x + 5)

= x³ + 4x² - 2x + 3 - x³ - 4x² + 7x - 5

= 5x - 2

b) A(x) + B(x) = (x³ + 4x² - 2x + 3) + (x³ + 4x² - 7x + 5)

= x³ + 4x² - 2x + 3 + x³ + 4x² - 7x + 5

= 2x³ + 8x² - 9x + 8.