If sin A = 3/4 , calculate cos A and tan A.

Let us draw a right angle triangle ABC. We know that, sin A = Substituting values we get, Let BC = 3k and AC = 4k. In right angle triangle ABC, By pythagoras theorem, ⇒ AC 2 = AB 2 + BC 2 ⇒ (4k) 2 = AB 2 + (3k) 2 ⇒ AB 2 = 16k 2 - 9k 2 ⇒ AB 2 = 7k 2 ⇒ AB = We know that, cos A = . tan A = . Hence, .