Question

Sin(55°+A)×sin(35°+B)-cos(55°+A)×cos(35°+B)=sin(A+B)

Answer 1

Step-by-step explanation:

- ( cos{55°+A}.cos{35°+B} - sin{55°+A}{35°+B} )

- cos(55°+A+35°+B)

- cos(90° +{A+B})

sin(A+B)

Answer 2

$\huge{\textbf{\blue{Solution is here.}}}$

Question: Sin(55°+A)×sin(35°+B)-cos(55°+A)×cos(35°+B)=sin(A+B)

Answer:- It proves that Sin(55°+A)×sin(35°+B)-cos(55°+A)×cos(35°+B) is equal to the sin(A+B).