If f (x) = 4x + 10, which expression represents f (x2 + 2) ?

In order to determine the answer to this item, we just have to substitute x² + 2 to all x's of the first function. That is,

f (x) = 4x + 10

will become,

f (x²+2) = 4 (x²+2) + 10

Simplifying will give us an answer of,

f (x²+2) = 4x²+18