How do you simplify $sin (90 + x)$ $sin(90 + x)$ ?

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Answer 1 · 2015-08-14T14:17:06

$sin (90 + x) = cos x$ $sin (90 + x) = cos x$

$sin (90 + x) = cos x$ $sin (90 + x) = cos x$

Method 1: Using plots of $sin x$ $sin x$ and $cos x$ $cos x$ . A shift of -90 degrees of $sin x$ $sin x$ gives you $cos x$ $cos x$

Method 2: $sin (A \pm B) = sin A cos B \pm cos A sin B$ $sin (A +- B) = sin A cos B +- cos A sin B$

How do you simplify sin(90+x)sin(90 + x)?