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 v + cos v sin u.
cos (v - u) = cos u cos v + sin u sin v
and
tan (u + v) = [tan u + tan v]/[1 - tan u tan v]

We got sin u = 4/5 & sin v = SQRT (7/13)

1. if cos u=3/5
cos v=5/13
then sin u=4/5 and sin v=12/13
then sin(v+u)=sinv cos u+cos v sin u
sin(v+u)=56/65
cos(v-u)=63/65
Tan u=4/3 and tan v=12/5 then
tan(u+v)=-56/33

posted by qqq

First Name

Similar Questions

1. 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 +
2. trig

Reduce the following to the sine or cosine of one angle: (i) sin145*cos75 - cos145*sin75 (ii) cos35*cos15 - sin35*sin15 Use the formulae: sin(a+b)= sin(a) cos(b) + cos(a)sin(b) and cos(a+b)= cos(a)cos(b) - sin(a)sin)(b) (1)The
3. 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
4. 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
5. math (trig)

Find sin(x/2) if sin(x)= -0.4 and 3pi/2 < or equal to (x) < or equal to 2pi Let's use cos 2A = 1 - 2sin2 A and we can match cos x = 1 - 2sin2 (x/2) so we will need cos x we know sin x = -.4 and x is in the fourth quadrant,
6. 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) =
7. precalculus

Find the tan(x), the sin (x + pi) if it is known that cos (x)=.6 and that (3pi)/2 less than x less than 2pi. Find the sine (2x), the tan (2x), and the cos (x/2) if it is known that cos (x)=.6 and that (3pi)/2 less than x less than
8. 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
9. trig

it says to verify the following identity, working only on one side: cotx+tanx=cscx*secx Work the left side. cot x + tan x = cos x/sin x + sin x/cos x = (cos^2 x +sin^2x)/(sin x cos x) = 1/(sin x cos x) = 1/sin x * 1/cos x You're
10. Trigonometry

a. Find the exact value of sin (theta - pi/6) b. Find the exact value of cos (theta - pi/4) c. For what numbers x, -2pi less than or equal to x less than or equal to 2pi does cos x = -1 d. What is the range of the cosine function?

More Similar Questions