Question

If sinA+sin B =2 what is the value of cos A - cos B=?​

Answer 1

Answer:

cos A - cos B = 4

Step-by-step explanation:

cos A =sin (90-A)

cos B =sin(90-B)

sin B = 2-sin A as per data given

sin A + sin B -2=0 as given

sin A + 2 - sin A =0

2sin A+2=0

2(sin A+1) =0

sin A+1=0

sin A=-1

sin B = 2- sin A as given

sin B = 2-(-1)

sin B=3

sin 90 = 1

cos A - cos B

(sin 90 - sin A) - (sin 90 - sin B)

1- sin A -(1- sin B)

1-sin A -1 + sin B

sin B - Sin A

cos A - cos B = sin B - sin A

3 -(-1)

3+1

4

cos A - cos B = 4