Find the exact value of the trigonometric function given tha
Find the exact value of the trigonometric function given that
sin u = 7/25
and
cos v = 3/5
.
(Both u and v are in Quadrant III.)
sin(u + v)
Solution
sin u=-7/25
here opposite=7 and hypotenuse=-25
Therefore adjacent= sqrt(7^2-(-25)^2)= sqrt(576)=24
Therefore cos u= -24/25
cos v= -3/5
Here adjacent=3 and hypotenuse=-5
THerefore opposite=sqrt((-5)^2-3^2= sqrt16)=4
Therefore sin v=-4/5
sin(u+v)=sinu cosv + cosu sinv
= (-7/25)(-3/5)+(-24/25)(-4/5)= (21/625)+(96/125)= 117/125
