Question

give that sin alpha =1/2 and cos beta1/2,then value of alpha +beta is? ​

Answer 1

Given:

• sinα = 1/2
• cosβ = 1/2

To find:

• α + β = ?

Solution:

Given , if sinα = 1/2 then α = 30° . Since , sin30° = 1/2

★ Proof:

→ sinα = 1/2

By comparing with sin30° = 1/2 , α = 30°

If cosβ = 1/2 then β = 60° . Since , cos60° = 1/2

★ Proof:

→ cosβ = 1/2

By comparing with cos60° = 1/2 , β = 60°

Now , finding α + β

• α + β = 30° + 60°

• α + β = 90°

Hence , α + β = 90°