# How do you find tan2A, given sin A = 3/5 and A is in QII?

##### 1 Answer

Dec 2, 2015

Find tan 2A, given

Ans:

#### Explanation:

Use the trig identity:

First, find

-->

Because A is in Quadrant II, its cos is negative.

Replace value of tan A = -3/4 into identity (1) -->

Check by calculator.

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