Solving Trig Equations

djsgarrett · **Joined:** Wed, 4 Apr 2012 20:15:46 UTC **Posts:** 10

I am stuck on this one.

csc^2 = 2cot + 4

I did the pythagorean identity and my equation becomes

1 + cot^2 = 2cot + 4 and ended up at

(cot - 3) (cot +1)=0

I think part of my answer is 2pik + 3pi/4, or is it pi k + 3pi/4? and 5pi/4? But what about cot=3?

Shadow · **Posted:** Wed, 4 Apr 2012 20:55:22 UTC

djsgarrett wrote:

I am stuck on this one.

csc^2 = 2cot + 4

I did the pythagorean identity and my equation becomes

1 + cot^2 = 2cot + 4 and ended up at

(cot - 3) (cot +1)=0

I think part of my answer is 2pik + 3pi/4, or is it pi k + 3pi/4? and 5pi/4? But what about cot=3?

Cotangent is 1 at ${3\pi\over 4}+\pi k$ , the only one on your list which is off is the ${5\pi\over 4}$ which gives a value of 1.

For 3, this doesn't fit into normal schema, so I'd just go with $\arctan{1\over 3}$ , that's about as good as you'll get.

djsgarrett · **Joined:** Wed, 4 Apr 2012 20:15:46 UTC **Posts:** 10

Thank you!

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Solving Trig Equations

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