Question

if sin(alpha+beta)=1 then cos(alpha-beta) can be reduced to​

Answer 1

Answer:

take help from this and at the place of cos u take sin

Answer 2

sin (a+b)=1

a+b =90⁰(sin1=90⁰)

a=90-b

cos (a+b)=cos (90⁰-b-b)

=cos(90-2b)

=sin 2b. {cos(90-a)=sina }