Question

why do sine functions correspond to the x-coordinate and cosine functions correspond to the y-coordinate?

Answer 1

correspond = produce, etc.

Answer 2

That's simply how the graphs operate. Cos(x) starts at 1 from 0, and Sin(x) starts at 0. Unless you are asking a more theoretical question, it relates to a sigma equation.

Answer 3

i mean that all my sine functions produce the x-coordinate on the unit circle....

Answer 4

aren't you reversed?

Answer 5

sine corresponds to the y on the unit circle. Cosine to the x.

Answer 6

yes, sorry - cosine is a/h, so in q1 it's the length of the x-axis, then? and sine is o/h so in q1 it's the length of the y-axis

Answer 7

well, you can also think out it like this, usually the angle( on the unit circle) is at the origin, and since the cosine function is adjacent over hyp, that means that its the run( you know from rise over run, slope) thus its the x coordinate. The sine is opp over hyp or the height( its the rise, from rise over run), thus it corresponds to the y coordinate. Hope that makes since :)

Answer 8

it does indeed. thank you very much.

Answer 9

hold on - i've got cosx+1=0, so cosx=-1, right???

Answer 10

yes

Answer 11

why does @sateillite ( http://bit.ly/oGsWtB) show it as cosx=1 then?

Answer 12

now, i assume you have to find what angles that occurs at right

Answer 13

it just says solve the problem i posted on that link