TRIG
posted by John .
if sin s = 5 /13
and sin t 3/5
s is in QIII
t is in QIV
find tan (st)
i got that tan (st)= 56/53
is that right? can someone check my work?

TRIG 
drwls
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 (st) = sin (st)/cos(st)
= [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.
Respond to this Question
Similar Questions

Trig
Given: cos u = 3/5; 0 < u < pi/2 cos v = 5/13; 3pi/2 < v < 2pi Find: sin (v + u) cos (v  u) tan (v + u) First compute or list the cosine and sine of both u and v. Then use the combination rules sin (v + u) = sin u cos … 
Trig.......
I need to prove that the following is true. Thanks (2tanx /1tan^x)+(1/2cos^2x1)= (cosx+sinx)/(cosx  sinx) and thanks ........... check your typing. I tried 30º, the two sides are not equal, they differ by 1 oh , thank you Mr Reiny … 
trig 26
simplify to a constant or trig func. 1. sec ²utan ²u/cos ²v+sin ²v change expression to only sines and cosines. then to a basic trig function. 2. sin(theta)  tan(theta)*cos(theta)+ cos(pi/2  theta) 3. (sec y  tan y)(sec y + … 
Trigonometry
Please review and tell me if i did something wrong. Find the following functions correct to five decimal places: a. sin 22degrees 43' b. cos 44degrees 56' c. sin 49degrees 17' d. tan 11degrees 37' e. sin 79degrees 23'30' f. cot 19degrees … 
Maths Calculus Derivatives
Find the first derivative for the following functions 1) f(x) = sin(cos^2x) cos(sin^3x) 2) f(x) = ( tan 2x  tan x ) / ( 1 + tan x tan 2x ) 3) f(x) = sin { tan ( sqrt x^3 + 6 ) } 4) f(x) = {sec^2(100x)  tan^2(100x)} / x 
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 x1 = sin^2x  cos^2x 3) 1/cosx  cosx = sin x tan x 4) sin x + tan x =tan x (1+cos x) 5) 1/1sin^2x= 1+tan^2 x How in the world do I prove this...please help... I appreciateyour … 
precalculus
For each of the following determine whether or not it is an identity and prove your result. a. cos(x)sec(x)sin^2(x)=cos^2(x) b. tan(x+(pi/4))= (tan(x)+1)/(1tan(x)) c. (cos(x+y))/(cos(xy))= (1tan(x)tan(y))/(1+tan(x)tan(y)) d. (tan(x)+sin(x))/(1+cos(x))=tan(x) … 
MathsSs triG
Consider sin(x360)sin(90x)tan(x)/cos(90+x) 1.A.SIMPLIFY sin(x360)sin(90x)tan(x)/cos(90+x) to a single trigonometric ratio B.hence or otherwise without using a calculator,solve for X if 0<X<360. sin(x360)sin(90x)tan(x)/cos(90+x) … 
math
Prove the identity: tan^2O/ 1 + tan^20 = sin^20 I get 1=1, but others have got sin^2=sin^2 Who's right?