Given sin30=1/2, use trig identies to find the exact value of
a. cos60
b. cos^230
c. csc pie/6
d. sec pie/3

Question

Given sin30=1/2, use trig identies to find the exact value of 
a. cos60
b. cos^230
c. csc pie/6
d. sec pie/3

anonymous · Answer

it has nothing to do with what sine is 
$$\cos(60^\circ)=\frac{1}{2}$$

anonymous · Answer

look at the unit circle on the last page of the attached cheat sheet
from that you can evaluate all the above trig functions

anonymous · Answer

All of the trig ratios are inextricably linked. That's how the trig identities were developed. So, yes, cos 60 can be related to sin 30. And a cheat sheet doesn't help anyone understand the relationships between the trig ratios. The identity required in this case is$$\cos \theta = \sin \left( 90- \theta  \right)$$

anonymous · Answer

How would I find $$\cos^230$$

anonymous · Answer

$$\cos ^2 30 = \cos30 \times \cos 30$$So if you apply the above identity twice you should be able to get the answer.