Question

sinc=sinD=2cos (C+D/2) sin(C-D/2) state true or false​

Answer 1

Correct Question :- sin C - sin D = 2 * cos (C+D/2) * sin(C-D/2) state true or false .

Answer :- True .

Explanation :-

Lets prove above formula .

taking LHS,

→ sin C - sin D

let C = A + B and D = A - B

so,

→ C + D = (A + B) + (A - B)

→ C + D = 2A

→ A = (C+D/2)

and,

→ C - D = (A + B) - (A - B)

→ C - D = 2B

→ B = (C - D/2)

now, we know that,

→ sin(A + B) - sin(A - B) = 2 * cosA * sinB

putting values now we get,

→ sin C - sin D = 2 * cos (C + D/2) * sin (C - D/2) (RHS) (Proved.)

Learn more :-

prove that cosA-sinA+1/cos A+sinA-1=cosecA+cotA

https://brainly.in/question/15100532

help me with this trig.

https://brainly.in/question/18213053