what is the relationship between the sine and cosine of complementary angles?

Question

campbell_st · Answer

well start by drawing a triangle and labeling some sides and angles 

|dw:1470103243536:dw|

so now that that is done... using the angle a what is 

sin(a) = ?

then look at the other angle 90 -a and find 
cos(90 - a)

what do you notice..?

hac138 · Answer

i jusr want a answer

jim_thompson5910 · Answer

http://www.mathwarehouse.com/sheets/trigonometry/sine-cosine-tangent/images/sohcahtoa-picture1.jpg

campbell_st · Answer

well that answer is in the diagram... just work it out

mathmale · Answer

Another approach:  recognize that 30 and 60 degrees are complementary angles, as they add up to 90 degrees.

Sorry, Your "I just want an answer" is a turn off.  If you just want answers then you apparently haven't read the OpenStudy Code of Conduct.  Let me know if and when you're willing to work, at which point I'd gladly help you.

hac138 · Answer

answer and ill reward points

mathmale · Answer

You don't get it.  Asking for direct answers violates everything OpenStudy represents.  I don't need points; I need for you to understand this math.

hac138 · Answer

ok

mathmale · Answer

Hope that means a change of attitude.
As before, 30 degrees and 60 degrees are complementary angles.
Please find the sine and cosine of each of them.  Do you see any pattern?

thesmartone · Answer

I kinda just explained to him right before he asked this question that we don't provide answers :P http://openstudy.com/study#/updates/579fed52e4b0a1a3dca78994

hac138 · Answer

i dont get it

mathmale · Answer

If you know the definitions of the sine and cosine functions, then surely you can find (or remember) the values of the sine and cosine functions for the angles 30 degrees and 60 degrees.  Rather than commenting, would you please show some actual work of your own?  If you use a calculator, explain how you found sin 30, cos 30, sin 60 and cos 60.