SAT Subject Test Mathematics Level 2

The answer is (D).

FUNCTIONS: DOMAIN AND RANGE

A   function    is  a   set of  ordered pairs   (x, y)  such    that    for each    value   of  x   there   is  one and only

one value   of  y.

The set of  all allowable   x   values  is  called  the domain. Note    that,   according   to  the SAT

directions, the domain  of  any function    f   is  assumed to  be  the set of  all real    numbers x   for

which   f(x)    is  a   real    number.

The corresponding   set of  all y   values  is  called  the range.

COMPOUND FUNCTIONS

The letter f is not the only letter used to designate a function, though it’s the most popular. Second
in popularity is the letter g, which is generally used in a question that includes two different
functions. Take a look at Example 2.

Example 2

If

and  ,  what    is  the value   of  h(g(6))?

1.

(A) 5.48

(B) 5.55

(C) 5.61

(D) 5.83