Answer
$7(x^{2}+1)(x^{2}-1)$
Work Step by Step
We are given the expression $7x^{4}-7$. First, we can use the distributive property to factor out 7, the greatest common factor of both terms.
$7x^{4}-7=7(x^{4}-1)$
If $a$ and $b$ are real numbers, we know that $a^{2}-b^{2}=(a+b)(a-b)$.
Therefore, $7(x^{4}-1)=7(x^{2}+1)(x^{2}-1)$.
In this case, $a=x^{2}$ and $b=1$.
