Question

express cos110 sin55 as sum or difference​

Answer 1

Answer:

i give you a example

sin 7α + sin 5α

= 2 sin (7α + 5α)/2 cos (7α - 5α)/2, [Since, sin α + sin β = 2 sin (α + β)/2 cos (α - β)/2]

= 2 sin 6α cos α