Answer :

The expression simplifies to a final value of 1. This is achieved through trigonometric identities and simplification of each term in the given expression.

Here is the step-by-step breakdown of the given expression:

[tex]\[ \frac{\cos(90\°+x) \cdot \sin(180\°+x)}{\tan 225\° - \cos^2(-x)} \][/tex]

Simplify each trigonometric term:

  cos(90°+x):

    Using the trigonometric identity, cos(90°+x) = -sin(x).

    So, cos(90°+x) = -sin(x).

  sin(180°+x):

    Using the trigonometric identity, sin(180°+x) = -sin(x).

    So, sin(180°+x) = -sin(x).

tan 225°:

    225° is in the third quadrant where tangent is positive. Using the trigonometric identity, tan(225°) = tan(180°+45°) = tan(45°) = 1.

    So, tan(225°) = 1.

cos²(-x):

    Cosine is an even function, so cos(-x) = cos(x).

    Therefore,cos²(-x) = cos²(x).

Substitute the simplified values into the expression:

[tex]\[ \frac{(-\sin(x)) \cdot (-\sin(x))}{1 - \cos^2(x)} \][/tex]

Simplify the numerator:

  -sin(x) . -sin(x)) = sin²(x)

Rewrite the denominator:

  Using the Pythagorean identity, 1 - cos²(x) = sin²(x).

  So, the expression becomes:

[tex]\[ \frac{\sin^{2} (x)}{\sin^{2} (x)} \][/tex]

Simplify the fraction:

  Since [tex]\(\frac{\sin^{2} (x)}{\sin^{2} (x)} = 1\).[/tex]

Therefore, the final simplified value of the given expression is:

[tex]\(\boxed{1}\)[/tex]

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