Question

in a triangle prove that bcos^2C/2+ccos^2B/2=s here s is semiperimeter of a triangle

Answer 1

Is it (bcos2c)/2

Answer 2

U know half angle theorems right
Use those equations to find the solution I got it by that method

Answer 3

As cos C/2=square root of (s(s-c))/ab. Cos B/2=square root of (s(s-b))/ac

Answer 4

From numerator and denominator b and c get cancelled

Answer 5

Then take s/a com on to get s/a(s-b+s-c) =s/a(2s-b-c) = (s/a)*a = s
hence proved

Answer 6

thank u
i did some mistake in the last step

Answer 7

Ur welcome

Answer 8

Any more problems