Posted by **John** on Thursday, March 5, 2009 at 8:09pm.

if sin s = -5 /13

and sin t -3/5

s is in QIII

t is in QIV

find tan (s-t)

i got that tan (s-t)= 56/53

is that right? can someone check my work?

- TRIG -
**drwls**, Thursday, March 5, 2009 at 11:58pm
If sin s = -5/13, and it is in the third quadrant, cos s = -12/13

s = 202.620 degrees

If sin t is -3/5, and t is in the fourth quadrant, cos t = 4/5.

t = 323.130 degrees

tan (s-t) = sin (s-t)/cos(s-t)

= [sin s cos t - sin t cos s]/

[cos s cos t + sin s sin t]

Crunch the numbers. You should get a rational fraction, but your 53 in the denominator looks fishy.

You answer should be 56/33.

## Answer This Question

## Related Questions

- Trig - Given: cos u = 3/5; 0 < u < pi/2 cos v = 5/13; 3pi/2 < v < ...
- trig - If sin A= 1/4 and sin B= -1/2, with A in QII and B in QIV, find tan(A+B)
- Trig Identities - Proving identities: 1) 1+ 1/tan^2x = 1/sin^2x 2) 2sin^2 x-1 = ...
- precalculus - For each of the following determine whether or not it is an ...
- Trigonometry - Please review and tell me if i did something wrong. Find the ...
- Trig....... - I need to prove that the following is true. Thanks (2tanx /1-tan^x...
- trig 26 - simplify to a constant or trig func. 1. sec ²u-tan ²u/cos ²v+sin ²v ...
- math - Prove the identity: tan^2O/ 1 + tan^20 = sin^20 I get 1=1, but others ...
- MathsSs triG - Consider sin(x-360)sin(90-x)tan(-x)/cos(90+x) 1.A.SIMPLIFY sin(x-...
- Maths Calculus Derivatives - Find the first derivative for the following ...

More Related Questions