To simplify the given expression, we can use trigonometric identities. Recall that \(\sec(x) = \frac{1}{\cos(x)}\). Therefore, \(\sec^2(x) = \frac{1}{\cos^2(x)}\). We can substitute this into the expression and simplify.
Solution Approach
Substitute \(\sec^2(x)\) with \(\frac{1}{\cos^2(x)}\).
Simplify the expression by combining like terms.
Step 1: Substitute \(\sec^2(x)\)
We start with the expression:
\[
\sin^2(x) \sec^2(x) - \sin^2(x)
\]
Using the identity \(\sec^2(x) = \frac{1}{\cos^2(x)}\), we can rewrite the expression as:
\[
\sin^2(x) \cdot \frac{1}{\cos^2(x)} - \sin^2(x)
\]
Step 2: Combine Like Terms
Next, we factor out \(\sin^2(x)\) from the expression:
\[
\sin^2(x) \left(\frac{1}{\cos^2(x)} - 1\right)
\]
We can simplify the term inside the parentheses:
\[
\frac{1}{\cos^2(x)} - 1 = \frac{1 - \cos^2(x)}{\cos^2(x)} = \frac{\sin^2(x)}{\cos^2(x)}
\]
Thus, the expression becomes:
\[
\sin^2(x) \cdot \frac{\sin^2(x)}{\cos^2(x)} = \frac{\sin^4(x)}{\cos^2(x)}
\]
Step 3: Use the Identity for \(\tan^2(x)\)
Recognizing that \(\frac{\sin^2(x)}{\cos^2(x)} = \tan^2(x)\), we can rewrite the expression as:
\[
\sin^2(x) \tan^2(x)
\]
Final Answer
The simplified expression is:
\[
\boxed{\sin^2(x) \tan^2(x)}
\]