Question

if Cos( A + B) = 0, then find the value of Sin (A - B).

Answer 1

Here is your Answer-

Explanation:

cos (a+b) =0

=> cos (a+b) = cos 90

=> a+b = 90

=> a = 90- b

Now

sin(a+b)

= sin(90-b-b)

= sin(90-2b)

= cos 2b     [as sin (90 - x) = cos  x]

Answer 2

Answer:

Step-by-step explanation:

Cos(A+B)=0

Cos90=0

Cos(A+B)=cos90

A+B=90

Sin(A-B)=cos(90-(A-B))

Sin(A-B)=cos(90-A+B)

Sin(A-B)=sin(A+B)

Sin(A-B)=sin(90)

Sin(A-B)=1