Question 62957
{{{(X - 3) (2X^3 - 15X - 6)}}}
Multiply the X by each of the terms in the second bracket then multiply the (-3) by each of the terms in the second bracket.
{{{ 2X^4 - 15X^2 - 6X - 6X^3 + 45X + 18}}}
Add like terms to get
{{{ 2X^4 - 6X^3 - 15X^2 + 39X + 18}}}