Multiply; Then Use Fundamental Identities to Simplify the Expression Below $$( \sin x + \cos x ) ( \sin x - \cos x )$$

question 83

Multiple Choice

Multiply; then use fundamental identities to simplify the expression below and determine which of the following is not equivalent.
$$( \sin x + \cos x ) ( \sin x - \cos x )$$

• A) \(2 \sin ^ { 2 } x - \sec ^ { 2 } x - \tan ^ { 2 } x\)
• B) \(\sin ^ { 2 } x - \cos ^ { 2 } x\)
• C) \(1 - 2 \cos ^ { 2 } x\)
• D) \(\csc ^ { 2 } x - \cot ^ { 2 } x - 2 \cos ^ { 2 } x\)
• E) \(1 - 2 \sin \left( \frac { \pi } { 2 } - x \right) \cos x\)

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