Question

2. If sin A = ½ , then the value of cot A is
(A) √3 (B) 1/√3 (C) √3/2 (D) 1

Answer 1

Answer:

According to the question,

Sin A = ½ … (1)

We know that,

… (2)

To find the value of cos A.

We have the equation,

sin2 θ +cos2 θ =1

So, cos θ = √(1-sin2 θ)

Then,

cos A = √(1-sin2 A) … (3)

cos2 A = 1-sin2 A

cos A = √ (1-sin2 A)

Substituting equation 1 in 3, we get,

cos A = √(1-1/4) = √(3/4) = √3/2

Substituting values of sin A and cos A in equation 2, we get

cot A = (√3/2) × 2 = √3