SOLUTION: I am using the fundamental identities to try to verify the following equation. It is a true statement but I find myself a little lost, probably on something basic algebra. I pri

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Question 1205416: I am using the fundamental identities to try to verify the following equation. It is a true statement but I find myself a little lost, probably on something basic algebra.
I primarily work on the left side and haven't really worked on the right side.
I know an identity could be verified by using many different methods, which is why the book I am using doesn't explain the process in the answers. So, your manner of verification may differ than what I am doing. Nevertheless, I'd appreciate any help.
In any case, here is the statement to be verified.
1 + sin theta/cot^2 theta = sin theta/csc theta - 1
Thank you very much for your help.

Found 3 solutions by ikleyn, mccravyedwin, MathTherapy:
Answer by ikleyn(52884) About Me  (Show Source):
You can put this solution on YOUR website!
.
I am using the fundamental identities to try to verify the following equation.
It is a true statement but I find myself a little lost, probably on something basic algebra.
I primarily work on the left side and haven't really worked on the right side.
I know an identity could be verified by using many different methods, which is why the book
I am using doesn't explain the process in the answers. So, your manner of verification
may differ than what I am doing. Nevertheless, I'd appreciate any help.
In any case, here is the statement to be verified.
1 + sin theta/cot^2 theta = sin theta/csc theta - 1
Thank you very much for your help.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


The identity in your post is (I copy it)

    1 + sin(theta)/cot^2(theta) = sin(theta)/csc(theta) - 1.


I read it this way - exactly as it is written in your post

    1 + sin%28theta%29%2Fcot%5E2%28theta%29 = sin%28theta%29%2Fcsc%28theta%29 - 1.



        This identity is INCORRECT, and I will show it right now.



Take theta = 45°.

Then in the left side,  cot(theta) = cot(45°) = 1;  so,  cot^2(theta) = 1, and the left side is

    1 + sin(45°) = 1 + sqrt%282%29%2F2.


The right side is  sin%2845%5Eo%29%2F%28%281%2Fsin%2845%5E0%29%29%29 - 1 = sin%5E2%2845%5Eo%29 - 1 = %28sqrt%282%29%2F2%29%5E2 - 1 = 2%2F4 - 1 = 1%2F2 - 1 = -1%2F2.


The left side 1 + sqrt%282%29%2F2 is not equal to the right side -1%2F2,  so the identity is not hold.

---------------

Double check your writing in your post.




Answer by mccravyedwin(409) About Me  (Show Source):
You can put this solution on YOUR website!
What you wrote was NOT an identity.  You wrote this:

1 + sin theta/cot^2 theta = sin theta/csc theta - 1

But you should have written this:

(1 + sin theta)/cot^2 theta = sin theta/(csc theta - 1)

Without the proper placing of parentheses, your problem
cannot be solved. Be careful!!!

OK, you want to start with the right side:

  

If you want to know how I got any step, just ask in the thank-you note.

Edwin

Answer by MathTherapy(10556) About Me  (Show Source):
You can put this solution on YOUR website!
I am using the fundamental identities to try to verify the following equation. It is a true statement but I find myself a little lost, probably on something basic algebra.

I primarily work on the left side and haven't really worked on the right side.

I know an identity could be verified by using many different methods, which is why the book I am using doesn't explain the process in the answers. So, your manner of verification may differ than what I am doing. Nevertheless, I'd appreciate any help.

In any case, here is the statement to be verified.

1 + sin theta/cot^2 theta = sin theta/csc theta - 1

Thank you very much for your help.

Sir Edwin manipulated the right side to match the left. Hence, I will do the same to the LEFT-SIDE to match the right side.

  

highlight%28%281+%2B+sin+%28theta%29%29%2F%28csc%5E2+%28theta%29+-+1%29%29%29 ----- Substituting csc%5E2+%28theta%29+-+1 for cot%5E2+%28theta%29

 ----- Factoring csc%5E2+%28theta%29+-+1 in denominator

 --- Substituting