Question

does cosine go from -pi/2 to pi/2? why?

Answer 1

what do you mean?

Answer 2

0 to pi

Answer 3

ok that's what my professor told me! :) but why is that so? and is that just for arctan? or all cosine?

Answer 4

it goes from \[-\pi/2,\pi/2\]the values range from 0 to 1 to 0 again

Answer 5

cosine 0 to pi sine -pi/2 to pi/2 and tan -pi/2 to pi/2

Answer 6

ok that makes sense, but why is it like that? what's it for?

Answer 7

when you draw the draphs its a 1:1 where horizontal line test fails hope this helps

Answer 8

it really requires a picture. hard to do here.

Answer 9

thanks to the both of you! that was a great help!!! =)