Which expression shows the correct multiplication of the following polynomilas? 3x (6x^2-3x+7)

Answer: 18x^3-9x^2+21x

Solution:

3x (6x^2-3x+7) =

Applying the distributive property in the multiplication to eliminate the parentheses:

(3x) (6x^2) + (3x) (-3x) + (3x) (7) =

(3*6) x^ (1+2) + 3 * (-3) x^ (1+1) + (3*7) x=

18x^3-9x^2+21x