if cosa=-24/25, pi/2

Question

if cosa=-24/25, pi/2<a<pi 
if tanB=9/40, pi<b<3pi/2
which quadrant is cos a and b? please help my finals is tomorrow

debbieg · Answer

All you want is the quadrants of a and b? They are given right in the problem.....

pi/2<a<pi   <---- what quadrant is that?
pi<b<3pi/2    <---- what quadrant is that?

Are you sure you have given the problem correctly?

anonymous · Answer

pi/2 to pi you can say 2nd quadrant and pi to 3pi/2 you can say 3rd quadrant

anonymous · Answer

no the given is correct. the problem is i don't know how to distuinguish wich quadrant is it. clue please?

debbieg · Answer

Have you studied the unit circle?

anonymous · Answer

yes i had

debbieg · Answer

|dw:1381313859704:dw|

debbieg · Answer

0 to pi/2 = qdrt 1
pi/2 to pi = qdrt 2
pi to 3pi/2 = qdrt 3
3pi/2 to 2pi = qdrt 4

You will want to make sure you know these, they come up a LOT. :)

anonymous · Answer

i get it so its in quadrant 2? am i right?

debbieg · Answer

a is, yes.

anonymous · Answer

and b is in quadrant 3 ahhh okay now i know hahha thanks a lot

debbieg · Answer

right!  and you're welcome :)