Question

sec theta is negative, which quadrant does it belong?

Answer 1

if sec(theta) is negative, then as sec(theta) = 1/cos(theta), it must be that
cos(theta) is also negative.

Now can you answer the question?

Answer 2

None of this makes since to me, i have done got like 10 people on here trying to explain it to me, but i cant understand it for some reason.

Answer 3

Go back to the definition of cos(theta).

Draw a unit circle centered at the origin, mark out an angle on that circle. What is the definition of cos(theta)?

It is the x-ordinate of the ray corresponding to that angle:


apologies for the klug of a diagram

Answer 4

Remember that definition of cos(theta)?

Answer 5

i.e., cos(theta) = x. This is why
cos(0) = 1, because when theta = 0, the ray corresponding to that value of theta lies along the positive x-axis and the point on the unit circle is (x,y) = (1,0).

Similarly, cos(pi/2) = 0, because there the point on the unit circle is (x,y) = (0,1)

Answer 6

making sense so far?

Answer 7

No. :/

Answer 8

i dont understand what the whole theta, cos, tan, etc stuff means.

Answer 9

Have a look at the top part of this article:
http://mathworld.wolfram.com/Cosine.html

You will need to understand what sin and cos means in order to answer your question, obviously.

Answer 10

ok, so is the answer Q3?