Factor completely.

25, x, to the power 4 , minus, 1
25x
4
−1

1 answer

To factor the expression \( 25x^4 - 1 \), you can recognize that it is a difference of squares.

The difference of squares can be factored using the identity:

\[ a^2 - b^2 = (a - b)(a + b) \]

In this case, we can rewrite \( 25x^4 - 1 \) as:

\[ (5x^2)^2 - 1^2 \]

Now, apply the difference of squares formula:

\[ (5x^2 - 1)(5x^2 + 1) \]

Now, observe that \( 5x^2 - 1 \) itself can be factored further, since it is also a difference of squares:

\[ 5x^2 - 1 = (5x^2 - 1^2) \]

So we can write:

\[ (5x - 1)(5x + 1) \]

Thus, the complete factorization of \( 25x^4 - 1 \) is:

\[ (5x - 1)(5x + 1)(5x^2 + 1) \]

The final factored form of \( 25x^4 - 1 \) is:

\[ (5x - 1)(5x + 1)(5x^2 + 1) \]