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2sinycosysec2y = tan2y

Plzzz solve this trig proof

1 Answer

5 votes
use:
2 sin y cos y = sin (y+y) + sin(y-y) = sin 2y + sin 0 = sin 2y

sec2y = 1 / cos2y

proof:

tan 2y = sin 2y / cos 2y = sin 2y sec 2y = 2 sin y cos y sec 2y
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