Question

find sin(x/2) if tanx=-12/5

Answer 1

1) Use SOHCAHTOA and Pythagorean theorem to find the third side of the triangle you are dealing with.

Answer 2

can i still do it with a negative?

Answer 3

so would the other side be 13?

Answer 4

YEs, I was just about to tell you how to find it, but you.... :)

Answer 5

and bye the way this should be using the half angle formula

Answer 6

So, now, ... hyp=13, but yes, you would plug in -13 into sin(x/2)= ...

Answer 7

Yes? half angle? Interesting assignment! So first tell me what will sin(x) equal ?

Answer 8

i dont know

Answer 9

how do i get it?

Answer 10

well thanks for the help :(

Answer 11

well, you found the hypotenuse, it is 13 (in matter of a distance, b/c distance is never negative) but as in quadrant-wise it is negative, so
Sin(x)=-12/-13=12/13

So now, use the half angle formula....