## Anyone able to help me with some trig?

Trigonometric ratios and functions, the unit circle, inverse trig functions, identities, trig graphs, etc.
masterrbc
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### Anyone able to help me with some trig?

So, i just found this forum, looks pretty helpful... anyway moving on...

Is anyone able to help me with some trig? I need help with Difference of Two Squares, some with Quadratic formula and some other things... I've only learned a bit of algebra, i was moved classes to a higher one where i am struggling anyway, here is the equation if anyone is able to help (Please include how you do it and any tips for doing it)

Solve 3tan^2(theta)-tan9theta)-2=0 and here is the domain 0(Less than or equal to)(Theta)(Less than or equal to)2(pie)

Anyone able to help?

stapel_eliz
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### Re: Anyone able to help me with some trig?

I need help with Difference of Two Squares...
Try this lesson on special factoring, including factoring differences of squares.
...some with Quadratic formula and some other things...
Try this lesson on the Quadratic Formula.
I've only learned a bit of algebra, i was moved classes to a higher one where i am struggling...
It's unfortunate that you were moved up before you were allowed to learn the necessary prerequisite content. This has condemned you, through no fault of your own, to struggle with material for which you have been left under-prepared.
Solve 3tan^2(theta)-tan9theta)-2=0 and here is the domain 0(Less than or equal to)(Theta)(Less than or equal to)2(pie)
I'll assume that you mean ''pi" (the Greek lower-case letter $\pi$ that stands for 3.14159...) rather than "pie" (the fruit-filled pastry dessert) in the domain interval.

So is this the equation?

. . . . .$\mbox{Solve }\, 3\tan^2(\theta)\, -\, tan(9\theta)\, -\, 2 \, =\, 0$

masterrbc
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Joined: Mon Apr 29, 2013 6:56 am
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### Re: Anyone able to help me with some trig?

Yes, I do know what Pi ,want before hand, hahah I was unable to write my equation properly, I got an error, but I think it was because I was using ,microfossils word... Anyway thanks for telling me about those lessons as well! but I know some of the things about trig and the equation is
Is the same, except it isn't Tan(9theta), it's just tan (theta) I didn't press shift for the nine.

masterrbc
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### Re: Anyone able to help me with some trig?

Also, there are no () i just did it to make it look neater, sorry!

stapel_eliz
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### Re: Anyone able to help me with some trig?

Also, there are no () i just did it to make it look neater, sorry!
Well, there are supposed to be parentheses! If your book didn't include them, it's being dangerously sloppy.

So the equation is as follows:

. . . . .$\mbox{Solve }\, 3\tan^2(\theta)\, -\, tan(\theta)\, -\, 2 \, =\, 0$

To solve, think about this like a regular quadratic:

. . . . .$\mbox{Solve }\, 3X^2\, -\, X\, -\, 2\, =\, 0$

Factor this quadratic in the usual manner, and set each of the factors equal to zero. Then back-substitute for the X, plugging the tan(@) back in for the X's. Then solve the resulting trig equation.

If you get stuck, please write back showing how far you got in working through the instructions. Thank you!

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