Question

Help?!

Answer 1

\[\cos(33degrees)\]=.084
Find cos(66degrees)

Answer 2

cos(2x)= 2((cosx)^2) - 1
just substitute values, u'll get

Answer 3

I STILL dont understand!

Answer 4

as ksram said, it is always true that
\[\cos(2\theta)=2\cos^2(\theta)-1\]
you know that
\[\cos(\theta)=\cos(33^0)=0.84\]
and therefore we must have
\[\cos(2\theta)=\cos(2\times 33)=\cos(66)=2\times \cos^2(33)-1\]
\[=2\times 0.84^2-1\] whatever that is

Answer 5

btw i checked and it is
\[\cos(33)=0.84\] rounded, not
\[\cos(33)=0.084\]