Question

sin^(2) x = (1 - cos x)/2 ?

Answer 1

\(\large sin^2x=\frac{1-cosx}{2} \)
\(\large 1-cos^2x=\frac{1}{2}-\frac{cosx}{2} \)
\(\large 0=cos^2x-\frac{cosx}{2}-\frac{1}{2} \)
\(\large 0=2cos^2x-cosx-1 \)

now it's a trig equation in quadratic form...
can you solve from here?

Answer 2

uhm..i just wanna know if sin ^(2) x is equal to (1-cosx)/2
according to the double angle formula??

Answer 3

oh...
you wanna know it the equation is an identity?

Answer 4

i'll just google it myself...thanks for replying! :)