C2: Trigonometrical equations
Maths and statistics discussion, revision, exam and homework help.
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C2: Trigonometrical equationsHi everyone, I’ve got a question
that I really don’t know what to do with! I’d be really grateful if someone could give me some pointers.
So I thought it would be the
identity that would be useful here. So I rearranged to
but then after that my mind froze and I really didn’t know what to do! 
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Re: C2: Trigonometrical equationsApplying knowledge of cos2x+sin2x=1, additionally.(Original post by Mr M)
Multiply each term by cos x. Now it is possible to form a quadratic equation in sin x.Last edited by dslc; 13-04-2012 at 12:06. -
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Re: C2: Trigonometrical equationsyou are going the right way. after where you got upto youget (3sinx/cosx)+2cosx=0 therefore (3sinx/cosx)=-2cosx so then 3sinx = -2cos^2x you should know what cos^2x is equivalent to and then when you substitute that you get a quadratic equation and get two values for sin x and then solve them for their given ranges. i dunno if im doing this right because you havent given the answer but i got sinx = -0.5 or 2
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Re: C2: Trigonometrical equationsI bet you blurt out the punchlines to jokes too.(Original post by dslc)
Applying knowledge of cos2x+sin2x=1, additionally. -
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Re: C2: Trigonometrical equationsWell actually, what you said was wrong.(Original post by Mr M)
I bet you blurt out the punchlines to jokes too.
It wasn't possible to form a quadratic without applying the information I added.
Apologies if I stole a little of your TSR thunder though. -
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Re: C2: Trigonometrical equations"The butler did it!"(Original post by dslc)
Well actually, what you said was wrong.
It wasn't possible to form a quadratic without applying the information I added.
Apologies if I stole a little of your TSR thunder though. -
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Re: C2: Trigonometrical equationsCould please help me with some statistic concepts?(Original post by dslc)
Applying knowledge of cos2x+sin2x=1, additionally. -
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Re: C2: Trigonometrical equationsI can try and help you with some statistics concepts, yes.(Original post by kingfisher)
Could please help me with some statistic concepts?
Perhaps consider starting a new thread however, given that they'd be unrelated to trigonometrical equations.
