SOLUTION: let sinx=4/5 where x is in quadrant ii. find (2x)

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Question 768055: let sinx=4/5 where x is in quadrant ii. find (2x)
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
Quadrant 2, the actual angle is pi-referenceAngle.
arcsin%284%2F5%29 gives the reference angle from 0 to pi. You would want first, x=pi-arcsin%284%2F5%29
and then you are looking for 2x, so
highlight%282%28pi-arcsin%284%2F5%29%29%29.


Approximately 253.7 degrees.