Question

 If sinA = 20/29 then find cosA.


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Answer 1

Answer:

cos A = 21/29

Step-by-step explanation:

Suppose , ΔABC is right angled at B

Given , sin A = 20/29

We know , sin A = Opposite / Hypotenuse

So , we can consider 20x as opp. and 29x as hypo.

By, pythagoreas theorum , we get Adjacent as +/- 21x

We know , cos A = Adj./Hypo.

So , cos A = +/- 21/29

(P.s. If you don't want to consider quadrant its +21x)