So I have an exam tomorrow, 50% of my grade. One of the 4 questions is gonna be a complex numbers problem. Now, my professor has a thing for making an easy thing hard, and the hardest part of the problem is gonna be figuring out sines and cosines of weird angles without a calculator. BUT, not weird in a sin(93.8) way, but more like sin(33/2 * pi) kind of way, multiples of common angles. I cannot find anywhere how do you do those (is it a - or a +), and I forgot if we learned that in high school.
Any trick / tip / video you can tell me to solve this, probably, the most trivial of problems?
reading the sticky would be very helpful
>>7681589
If you mean the rules, it's really not a homework problem, it's just one thing that I cannot find, and I need it for tomorrow. If you mean the sticky as in finding the answer in the wiki, yeah.. I'm better of if I keep googling.
I just thought it's a simple thing someone could explain in one sentence.
google "trig identities"
>>7681611
fuck you
>>7681603
so ask your prof. this is a homework thread.
>>7681617
Oh my god, I'm cured from spamming your board forever! Fuck off dude, hide the thread.
Take these numbers 0 1 2 3 4
Take the root of each 0 √2 √3 2
Divide by two 0 √2/2 √3/2 1
Wow. Now put these numbers on the axis. Count in π/12 for max pleasure, and tadaaa, you know everything.
>>7681673
>Sqrt(2)/2
Not simplifying.
REEEEEEEEE
>>7681786
>putting square roots in the denominator
Kill yourself
>>7681555
>but more like sin(33/2 * pi) kind of way, multiples of common angles.
Just use formulas, kek. It's easy.
>not realizing that sin(33/2 * pi) = sin(1/2 * pi) = 1
