Question

show that if a,b and c are the interior angles of a triangle,then show that sin(b+c/2) =sin(a/2)

Answer 1

a + b + c = 180 (ASP)

b + c = 180 - a

(b + c)/2 = (180 - a)/2 = 90 - a/2

sin (b+c/2) = sin(90 - a/2) = cos(a/2)

I think that what I proved is correct so check your question please

if it is correct, then please mark as Brainliest

Answer 2

Answer:

Sin[(B+C)/2]

Since A+B+C=180 for interior angles of triangle ABC.

then B+C=180-A.

NOW Sin [(180-A)/2]

=Sin[90-(A/2)]