| 
 
 
| Question 817520:  Use the given values to evaluate (If possible) all six trigonometric functions:
 Cos(-x)=(8/17),sin x<0
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! Use the given values to evaluate (If possible) all six trigonometric functions: Cos(-t) = (8/17) , sin(t) < 0
 sin(t) is negative in QIII and in QIV
 cos(-t) is positive in QIV
 x is positive and y is negative in QIV
 -------
 cos = x/r so x = 8 and r = 17
 -------
 Therefore y = sqrt[17^2-8^2] = 15
 So, y is -15
 -------------
 sin(t) = y/r = -15/17
 cos(t) = x/r = 8/17
 tan(t) = y/x = -15/8
 ----
 csc(t) = r/y = -17/15
 sec(t) = r/x = 17/8
 cot(t) = -8/15
 ------------------------
 Cheers,
 Stan H.
 ===========
 | 
  
 | 
 |