Question

If A+B+C=180。, prove that sin^2[A]+sin^2[b]+sin^2[C]=2+2cosAcosBcosC

Answer 1

\(a +b+c =\pi\)
\( b = \pi -(a+c)\)
\[sin^2a + sin^2(\pi -(a+c) ) + sin^2c\]
\[sin(a+c) = sina*cosc +cosa*sinc\]
\[sin^2(a+c) = sin^2a*cos^2c + cos^2a*sin^2c + 2sina*cosa*cosc*sinc\]
This should Help

Answer 2

mellinia u must reply and give medal to Ishaan as he has atleast helped u

Answer 3

oh.

Answer 4

oh.