Question

a) sin2c=2sinx cosx
b) sin(π/2 - x) =cosx

REPEDE VA ROG!!​

Answer 1

$\sin(2x) = 2 \sin(x) \cos(x) \\ \\ \sin(2x) = \sin(x \times x) \\ \\ \sin(2x) = \sin(2x)$

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b)

$\sin( \frac{\pi}{2} - x ) = \cos(x) \\ \\ \sin( \frac{\pi}{2} ) \cos(x) - \cos( \frac{\pi}{2} ) \sin(x) = \cos(x) \\ \\ 1 \cos(x) - 0 \sin(x) = \cos(x) \\ \\ \cos(x) - 0 = \cos(x) \\ \\ \cos(x) = \cos(x)$

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