Question

Need answer to pictured problem! The answer should be in reference to trig identities

Answer 1

Step 1. The expression that we have is:

$cos^2(5x)$

and we need to find the equivalent expression.

Step 2. The trigonometric identity we will use to solve this problem is:

$cos^2A=1-sin^2A$

In this case:

$A=5x$

Step 3. Applying the trigonometric identity to our expression, substituting 5x in the place of A:

$cos^2(5x)=\boxed{1-sin^2(5x)}$

This is shown in option d).

Answer:

$\boxed{d)\text{ }1-s\imaginaryI n^2(5x)}$