Advanced Math practice question

Answer: 2

The denominator x² − 4 = (x − 2)(x + 2) is 0 at x = 2 and x = −2: two values. (Cancelling the common factor does not remove the restriction at x = −2.)

Common wrong answers

If you answered 0

0 assumes the expression is defined everywhere.

If you answered 1

1 counts only x = 2, forgetting that x = −2 also makes the original denominator 0.

If you answered 4

4 is the constant in the denominator, not a count.

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