Answer:
see explanation
Step-by-step explanation:
The volume (V) of the cuboid is calculated as
V = (2x + 5)(3 - x)(x + 1)
= (3 - x)(2x + 5)(x + 1) ← expand the pair of factors using FOIL
= (3 - x)(2x² + 7x + 5)
= 3(2x² + 7x + 5) - x(2x² + 7x + 5) ← distribute parenthesis
= 6x² + 21x + 15 - 2x³ -7x² - 5x ← collect like terms and rearrange
= 15 + 16x - x² - 2x³
