Trig
posted by Heather .
What is the exact value of tan(s+t) if sin(s+t)=56/65. And cos(s)=5/13 and sin(t)=4/5. Everything is in the first quadrant

draw the triangles and you will see that
tan(s) = 12/5
tan(t) = 4/3
Now just plug in your sum formula:
tan(s+t) = (tan s + tan t)/(1  tan s * tan t)
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 … 
Mathematics  Trigonometric Identities
Let y represent theta Prove: 1 + 1/tan^2y = 1/sin^2y My Answer: LS: = 1 + 1/tan^2y = (sin^2y + cos^2y) + 1 /(sin^2y/cos^2y) = (sin^2y + cos^2y) + 1 x (cos^2y/sin^2y) = (sin^2y + cos^2y) + (sin^2y + cos^2y) (cos^2y/sin^2y) = (sin^2y … 
simple trig
If sin(theta)=[sqrt(70)]/7 and theta is in Quadrant two, find the exact numerical value of tan theta without using a calculator. I got tan(theta)=[sqrt(294)]/42 Is that right? 
easy trig
If sin(theta)=[sqrt(70)]/7 and theta is in Quadrant two, find the exact numerical value of tan theta without using a calculator. I got tan(theta)=[sqrt(294)]/42 Is that right? 
TRIG!
Posted by hayden on Monday, February 23, 2009 at 4:05pm. sin^6 x + cos^6 x=1  (3/4)sin^2 2x work on one side only! Responses Trig please help!  Reiny, Monday, February 23, 2009 at 4:27pm LS looks like the sum of cubes sin^6 x + cos^6 … 
Alg2/Trig
Find the exact value of the trigonometric function given that sin u = 5/13 and cos v = 3/5. (Both u and v are in Quadrant II.) Find csc(uv). First of all, I drew the triangles of u and v. Also, I know the formula of sin(uv) is sin … 
math
Use the exact values of the sin, cos and tan of pi/3 and pi/6, and the symmetry of the graphs of sin, cos and tan, to find the exact values of si pi/6, cos 5/3pi and tan 4pi/3. I have found the answers to the first three using the … 
math
Use the exact values of the sin, cos and tan of pi/3 and pi/6, and the symmetry of the graphs of sin, cos and tan, to find the exact values of sin pi/6, cos 5/3pi and tan 4pi/3. I have found the answers to the first three using the … 
Math Trig
1. Determine the exact value of cos^1 (pi/2). Give number and explanaton. 2. Determine the exact value of tan^1(sq. root 3). with explanation. 3. Determine exact value of cos(cos^1(19 pi)). with explanation. 4. Determine the exact … 
Trig hep, please? Thank you!
1. Find the exact value of sin(195(degrees)) 2. If cot2(delta)=5/12 with 0(<or =)2(delta)pi, find cos(delta), sin(delta) , tan(delta). 3.find the exact value of sin2(x) if cos(x)= 4/5. (X is in quadrant 1) 4. Find the exact value …