PS : Basics

[k_rohit]

Which of the following must be true ?
a) A linear equation in one variable always gives a unique value of x.
b) A quadratic equation in one variable always gives two unique value of x.
c) (Even)^n is always even, where n is an integer.
d) (Odd)^n can never be even, where n is an integer.
e) |x| is always positive

[Scott@TargetTestPrep]

Which of the following must be true ?
a) A linear equation in one variable always gives a unique value of x.
b) A quadratic equation in one variable always gives two unique value of x.
c) (Even)^n is always even, where n is an integer.
d) (Odd)^n can never be even, where n is an integer.
e) |x| is always positive

Solution:

Choice D is correct since for any other answer choices, you can find at least one counterexample to show the statements in those choices is not correct. Here is a counterexample for each of the answer choices other than D.

A) x = x + 1

B) x^2 = 0

C) 2^0

E) |0|

Answer: D