SAT Subject Test Mathematics Level 1

Example 3

LOGIC

If you encounter a logic question, it is likely that about all you’ll have to know
is the so-called contrapositive. That’s what Example 4 is getting at.

Example 4

To  multiply    complex numbers,    use FOIL.   (Review chapter 4   if  you

forgot  what    FOIL    stands  for.    It’s    a   way of  remembering the order   of

operations  for multiplying binomials:  first,  outer,  inner,  last.)  Just

remember    again   to  take    that    extra   step    of  changing    i^2     to  −1:

The answer  is  (A).

1.

1. “If  p,  then    q”  is  logically   equivalent  to  which   of  the following?

I. If   q,  then    p.

II. If  not p,  then    not q.

III. If not q,  then    not p.

(A) I   only

(B) III only