Multiply using the rule for finding the product of the sum and difference of two terms.
-$$( x + 1 ) ( x - 1 )$$
A) $x ^ { 2 } - 2$
B) $x ^ { 2 } + 2 x - 1$
C) $x ^ { 2 } - 2 x - 1$
D) $x ^ { 2 } - 1$

Question

Quizplus · Accepted Answer

The rule for finding the product of the sum and difference of two terms is $(a + b)(a - b) = a^2 - b^2$. Applying this rule here with $a = x$ and $b = 1$, we get $x^2 - 1^2 = x^2 - 1$.

Multiply Using the Rule for Finding the Product of the Sum