Tuesday, July 04, 2006

Problem Solving - 5

If |x| > 3, which of the following must be true?

A). x>3

B). x<3

C). x=3

D). x is not equal to 3

E). x<-3

Answer - D

A,B,E - Ruled out - a modulus sign in the question=>cannot have a single signed (can always find a solution with the opposite sign )

When x is positive ----- x >3

When x is negative ---- x <-3

Thus x can never be equal to 3.