<PRE><B>Question 930389</B>
Let theta be an angle in quad III such that sec theta = -13/5. Find the exact values of cot theta and sin theta?
 
-----
Note:: both x and y are negative in QIII
---
By definition, sec = r/x
Since sec(t) = -13/5, r = 13 and x = -5
Then y = -sqrt[13^2-5^2] = -sqrt(144) = -12
-----
Ans:
cot(t) = x/y = -5/-12 = 5/12
sin(t) = y/r = -12/13
-----------------------------
Cheers,
Stan H.
--------------</PRE>