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# Optimization: Trig functions

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1. 8(sinX)^-2.cosX - 4(cosX)^-2.sinX = 0

is my derivative

How do I solve for X easily?
2. (Original post by chrislpp)
8(sinX)^-2.cosX - 4(cosX)^-2.sinX = 0

is my derivative

How do I solve for X easily?

Multiply both sides by , then divide both sides by

You will get Solve it to get the solutions.

Sorry for not replying to your previous thread, i did saw that you quoted me about this question but i was busy so couldn't help.
3. Add 4(cosX)^-2.sinX to both sides (to get an equality), get rid of the fractions, divide one side by the other.
4. (Original post by raheem94)
.. Solve it to get the solutions.
This is a bit close to a full solution if you ask me...
5. (Original post by DFranklin)
This is a bit close to a full solution if you ask me...
I understand it is close to a full solution. Actually he asked me this question on another thread, but i was busy so can't reply neither did anyone else helped him with it, so i thought that he has been stuck on it for a long time now and as no one was helping him so i decided to give him enough detail to finish off the question.

Sorry for it though.
6. (Original post by raheem94)
I understand it is close to a full solution. Actually he asked me this question on another thread, but i was busy so can't reply neither did anyone else helped him with it, so i thought that he has been stuck on it for a long time now and as no one was helping him so i decided to give him enough detail to finish off the question.

Sorry for it though.
No worries.

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