# How do you find the exact values of sin 2u, cos 2u, and tan 2u using the double-angle formulas?

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sin u= -4/5, 3#pi# /2 < u < 2#pi#

sin u= -4/5, 3

##### 1 Answer

Jun 23, 2018

#### Explanation:

(cos 2u is negative because u = - 53.13, so, 2u lies in Quadrant 3)