If calculate cos A and tan A.

Given: Sin A

We know that,

Or

Let,

Side opposite to angle θ = BC =3k

and Hypotenuse = AC =4k

where, k is any positive integer

So, by Pythagoras theorem, we can find the third side of a triangle

⇒ (AB)² + (BC)² = (AC)²

⇒ (AB)² + (3k)² = (4k)²

⇒ (AB)² + 9k² = 16k²

⇒ (AB)² = 16 k² – 9 k²

⇒ (AB)² = 7 k²

⇒ AB =k√7

So, AB = k√7

Now, we have to find the value of cos A and tan A

We know that,

Here, θ = A

The side adjacent to angle A = AB =k√7

Hypotenuse = AC =4k

So,

Now,

We know that,

The side opposite to angle A = BC =3k

The side adjacent to angle A = AB =k√7

So,