SOLUTION: how can i find the exact value of pie/8?

Question 635145: how can i find the exact value of pie/8?
Answer by jsmallt9(3758) (Show Source): You can put this solution on YOUR website!
Short answer: You can't. is an irrational number. Neither it nor it divided by a whole number like 8 can ever be expressed exactly (other than with and and .

But I think you left out part of the problem. I think you are supposed to find
or or ...
which can be found exactly. (Hint: Use a "Half-Angle" formula.)

If my hint is not enough help for you to figure it out, please re-post the full problem.

P.S. If you are really sure that you posted the full, correct problem, then the problem is bad. To make sense the problem must ask you to find one or more of...
or or ...
Are you sure it doesn't say to find all the trig function values for ?

Once you know which function(s) you are supposed to find, then you have the right idea with the Half-angle formulas.

You solution for has an error:

(Note: It is not necessary to change and/or into degrees to do these problems.)
RELATED QUESTIONS
sin(x)=8/17 find the exact value of tan(2x) pie/2... (answered by lwsshak3)

Find the exact value of the expression. 2sec-pie/3 cos pie/3 -tan pie/6 (answered by stanbon)

find the exact value of the expression... (answered by checkley77,jim_thompson5910)

Find the exact value of cot... (answered by Fombitz)

Find the exact value of... (answered by jim_thompson5910)

find the exact value of tan(-3... (answered by jim_thompson5910)

Find exact value of:... (answered by stanbon)

7. Suppose sin a= -4/5 where 3pie/2 (answered by Alan3354)
Find exact value of Trigonometry functions using the Unit Circle. tan(pie/3). I know... (answered by solver91311,stanbon)