Question

if A+B=90° Then find value of SinA+SinB

Answer 1

A+B=90°

sinA+sinB
we can write it by taking sin common

Sin(A+B)

And According to Question A+B=90

so,
Sin(90)
And Sin 90°= 1

so,
SinA+SinB=1

Answer 2

Answer:

Then find value of SinA+SinB if A + B = 90° is √2.

Step-by-step explanation:

In order to solve the above question, we need to know some of the trigonometric formulae:-

According to the question, A + B = 90° and we need to find the value of sinA+ sinB

From A + B = 90' we can evaluate the value of B in terms of A i.e. 

B = 90° - A

Let x = sinA + sinB

⇒ sin A + sin (90' - A)

⇒ sin A + cos A

taking derivation on both sides we get,

dx/dA = cos A - sin A = 0

or, cos A = sin A

We know only if the angle is 45° then the above situation will satisfy.

Therefore, sin A + sin B

       = sin 45° + sin 45°

       = 1/√2 + 1/√2

        = √2 (Ans)