Question

3. If A = 6x^2 - x^2 + 4x + 8 and B = 2x^3 + x - 5 then A - B equals

(1) 4x3 - x2 + 3x – 13
(2) 8x3 - x2 + 5x + 3
(3) 4x3 – x2 + 3x + 13
(4) 8x3 + 3x + 3​

Answer 1

Hi there!

`\large\boxed{(3) \text{ } 4x^(3) - x^(2) + 3x + 13}`

Given:

A = 6x³ - x² + 4x + 8

B = 2x³ + x - 5

Find A - B by subtracting the two equations. Subtract like-terms:

6x³ - x² + 4x + 8 - (2x³ + x - 5)

Simplify:

6x³ - x² + 4x + 8 - 2x³ - x + 5 =

4x³ - x² + 3x + 13. The correct choice is 3.