SAT Subject Test Mathematics Level 2

When    it  comes   to  functions,  pay close   attention   to  order   and parentheses.

Notice also that there’s a difference between h(g(x)) and h(x)g(x). In the former expression, a
hierarchy is indicated: The function g is inside the parentheses of function h, so you apply g first, and
then you apply h to the result. In the expression h(x)g(x), however, the two functions are written side
by side, which indicates multiplication. You apply the function h to 6, and you apply the function g
to 6, and then you multiply the results:

So when it comes to functions, be sure to pay close attention to order and parentheses.

MAXIMUMS AND MINIMUMS

Another typical functions question is one that asks for a minimum or, as in Example 3, maximum
value of a function.

Example 3

1. What is  the maximum value   of  f(x)    =   3   −   (x  −   2)^2?

(A) −3

(B) −1

(C) 1

(D) 3

(E) 5