Solve:

6sinsquared x + 5sinxcosx - 5cossquared x = 1

just cant seem to get it, any help is GREATLY APPRECIATEDD

thankuu !

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- May 29th 2009, 09:19 PMiihartheroSolve trig equation please help
Solve:

6sinsquared x + 5sinxcosx - 5cossquared x = 1

just cant seem to get it, any help is GREATLY APPRECIATEDD

thankuu ! - May 29th 2009, 09:55 PMamitface
Let and , and move the 1 over.

Then you have . That factors nicely. See if you can work from there. - May 29th 2009, 10:14 PMiiharthero
sorry i dont no if this is a really stupid question, feeling realli thick today

but wat do u mean wen u say move the 1 over ? - May 29th 2009, 10:22 PMEnedrox
I think he actually made a mistake.

If you let and

You get or which do not factorise nicely. - May 29th 2009, 10:37 PMiiharthero
yea..thats wat i thought..i donno

please any one if you can help ?

thanksss - May 29th 2009, 10:44 PMEnedrox
I used a program to simplify the original equation, and it came out with:

I tried working it out like this first:

Let's fisrt get rid of the :

But it didn't give anything.

Then I found that the calculator finished up with 2x, so I gave a go to double angle formulas.

Except I think I might have done an error (graph of step 2 and step 3 are different, dunno why) - May 29th 2009, 10:54 PMiiharthero
well thanx for taking da time to help me , wow i dont realli get wat uve done, looks extremely complicated, i dont think the question is meant to be that complicated because i can do the qs before and afta it

if it helps the solution to the question is 35 degrees 9 minutes, 120 degrees 24 minutes, 215 degrees 9 minutes and 300 degrees and 24 minutes

i jst dont no how to get there

thanx tho ! - May 29th 2009, 11:26 PMEnedrox
Well, what I've done is using the trig identities (mainly: )

I also used the double angle formulas:

- May 30th 2009, 01:48 AMs_ingram
Hi iiarthero,

the solution is attached. - May 30th 2009, 02:44 AMiiharthero
thanx for ur help !!!!!