cos(π/6)

Question

cos(π/6)

hero · Answer

What do you have to do with that? Find the exact answer?

anonymous · Answer

cos(30)=1/2

anonymous · Answer

no i can type into a calculator and get the exact answer but i need to do it on paper so that it equals to radical 3/ 2

anonymous · Answer

no @rathanreddy that would be the sin(30)

hero · Answer

@rathanreddy, that's not correct

anonymous · Answer

ya  root 3/2

anonymous · Answer

what i need help with is how to solve it algebraically

hero · Answer

I don't think there's a computational process to this @hellysos. You just have to memorize the unit circle.

hero · Answer

However, it is easier to simplify if you let pi = 180, then you know 30 is the angle.

anonymous · Answer

i figured that, my professor suggested relating the angles to triangles and solving them with the pythagorean theorem

hero · Answer

Actually, you can probably use right trangles to do it.

anonymous · Answer

if i use triangles then 1^2 +1^2= 2

anonymous · Answer

and that is not radical 3/2

anonymous · Answer

so im at a stump

hero · Answer

You just have to figure out the ratio of the sides. If you have a right triangle, with theta = 30 degrees then:

|dw:1374687967210:dw|