SOLUTION: I am struggling with converting trig identities. The problem I have is cos(theta)=u/3 and I am supposed to come up with the remaining 5 identities. I was able to get sin(theta)=(sq

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Question 813888: I am struggling with converting trig identities. The problem I have is cos(theta)=u/3 and I am supposed to come up with the remaining 5 identities. I was able to get sin(theta)=(sqroot of 9-u^2)/u and tan(theta)=(sqroot of 9-u^2)/u but when I try the cot, sec, and csc all of my answers are wrong. for example i put cot(theta)=u/(sqroot of 9-u^2) because cot is the reciprocal of tan. please show me what I'm doing wrong.
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi, Perhaps it is the format

Re Reply: Generally, leaving a radical in the denominator is unacceptable

 as the correct answer, as rational denominators are wanted.

 cosθ  = u%2F3   secθ  = 3%2Fu 

 sinθ  = sqrt%289-u%5E2%29%2F3  cscθ  = 3%2Fsqrt%289-u%5E2%29+=+3sqrt%289-u%5E2%29%2F%289-u%5E2%29

 tanθ  = sqrt%289-u%5E2%29%2Fu    cotθ  = +u%2Fsqrt%289-u%5E2%29=+%28u%2Asqrt%289-u%5E2%29%29%2F%289-u%5E2%29+