Trig
posted by Tabitha .
Find the exact value of sin75degrees+ sin15degrees.

One way, if you've learned some trig properties... sin x + sin y = 2*sin((x+y)/2)*cos((xy)/2)
So sin(75) + sin(75) = 2*sin(45)*cos(30) = 2*sqrt(2)/2*sqrt(3)/2 = sqrt(6)/2
Respond to this Question
Similar Questions

trig
give exact value of cos 75 degrees. give exact value sin 15 degrees. give exact value sin 225 degrees. You will have to use the addition relations here. Notice 75 is 30 +45, 15 is 4530, and 225 is 180 + 45. I will be happy to critique … 
trig/pre calc
hello, i don't quite understand how to do this type of problem: 1. find the exact value of sin (pi/3). even more confusing is 2. find the exact value of csc^1 (1). i would appreciate any kind of help! thank you! 
trig
use the unit circle to find the exact value for all the trig functions of è=2ð/3. 
trig
find the exact value of cos 3.14/8 
Trig
1. Establish the identity: sin(theta+3pi/2)=cos(theta) 2. Find the exact value of 2(theta) if sin(theta)=5/13 3. Show that: csc2(theta)cot2(theta)=tan(theta) 4. Find the exact value of tan(cos^1(square root of 3/2) 5. Approximate … 
trig
2cos^2 22.51 (find exact value) 
Math
Find the exact value of sin75degrees using sum identity of sine 
trig
How do I find the exact value of sin (pi/24)? 
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 … 
trig
if (12,5) is a pointon the terminal side of an angel 0 find the exact value of six trig funcation of 0