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anonymous
 one year ago
I desperately need someone to help me with Trig!!! please!!! FAN AND MEDAL!!
anonymous
 one year ago
I desperately need someone to help me with Trig!!! please!!! FAN AND MEDAL!!

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triciaal
 one year ago
Best ResponseYou've already chosen the best response.1review some basics dw:1432906516081:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0That's a good graph. I get that for the most part...but I have no idea how to verify identities

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0for example csc(theta)  sin(theta) = cot(theta) cos(theta) I have to verify the identity and find the domain

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1@B_O_R_E_D Are you familiar with the basic identities?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0sort ofish...they are confusing

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Can you post what you know? We'll see if you have everything you need.

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Sorry, I was expecting you to type what YOU know, not what's online.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0its not online its just a word doc...I can type if youd like

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Sorry, I was expecting you to type what YOU know, not what's online. Besides, I only open/display .jpg files.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay...hang on I'll type it

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Yes, it would be nice. Because typing them out also helps you getting familiar with them.

triciaal
 one year ago
Best ResponseYou've already chosen the best response.1dw:1432907494538:dw

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1@triciaal what you posted is a very good review of the basics, before even the question was posted. Genial!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0csc(theta) = 1/sin(theta) sin(theta) = 1/csc(theta) sec(theta) = 1/cos(theta) cos(theta) = 1/sec(theta) tan(theta) = 1/cot(theta) cot(theta) = 1/tan(theta)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0reciprocal identities

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Did you miss out anything? There is at least one more that you need.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0tan(theta) = sin(theta)/cos(theta) (Tan identity) cot(theta) = cos(theta)/sin(theta) (Cot Identity)

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Good, we'll need these and... one more...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0that's all I've learned

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1dw:1432904305976:dw This is extracted from @triciaal 's post. Can you use Pythagoras Theorem to write down the missing identity?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ummm sin(theta)/tan(theta)?

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Think Pythagoras's theorem!

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1dw:1432904481376:dw Perhaps I missed out the 90 deg. angle didn't help. Pythagoras theorem says that the sum of the squares of the two legs of a right triangle equals the square of the hypotenuse. Can you figure out something?

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Hint: use the diagram I extracted from @Triciaal 's post.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I really have no idea... ummm did I miss cos?

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1more hint: dw:1432904684712:dw Pythagoras theorem says \(a^2+b^2=c^2\)

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1ok, use the diagram below and use Pythagoras theorem: dw:1432904785881:dw It would be \(sin^2(x)+cos^2(x) = 1\) This is the missing identity. Have you seen that before?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ohhhhh no I haven't....They have just introduced trig to me in this last unit for the year...everything I've done this year has been alg2

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1But now you understand why this is true?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0im leaning toward less

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay...so I know we have to use a reciprocal identity

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1The identity comes from the definition of sin and cos. With a hypotenuse of 1, the identity is just an application of Pythagoras. In any case, you only have to know it, most of the time you're not expected to prove it.

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Now back to the question. csc(theta)  sin(theta) = cot(theta) cos(theta) In verifying identities, we usually start from one side. In this case, we can start from the left.

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1If we can show that the left side is identical to the right, we're done.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay.. so I think I need to get like similar terms or something so would I replace sin(theta) for 1/csc(theta) ???

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Exactly, that's an excellent start. A lot of the time, this strategy works!!!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yay!! okay so csc(theta)  1/csc(theta) = cot(theta) cos(theta)

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1I don't see your reasoning, can you explain?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I replaced sin...so I was just filling that in the equation

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1If we start with the left, we don't usually write the right hand side, because equality is not yet proven. We write (I'll use x instead of \(\theta\), saves me time.) as your first step: csc(x)sin(x) = 1/sin(x)  sin(x)

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Are you at ease with adding fractions, such as 1/3 + 3?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0oh! I put it on the wrong side yeah those are fine

mathmate
 one year ago
Best ResponseYou've already chosen the best response.11/33 = 1/3  3^2/3 = (13^2)/3 Does this make sense to you?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay.... oh yes! I see what you did okay

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Now you need to do the same with 1/sin(x) and continue the following \( csc(x)sin(x) = \frac{1}{sin(x)}  sin(x)\)

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1R U stuck or R U working on it?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0trying to work on it...but im still stuck

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Well... it's similar to the 1/3 example: \(\large csc(x)sin(x) = \frac{1}{sin(x)}  sin(x)=\frac{1sin^2(x)}{sin(x)}\)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay....so that's how you verify it?

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1or \(\large csc(x)sin(x) = \frac{1}{sin(x)}  sin(x)=\frac{1}{sin(x)}\frac{sin(x)}{sin(x)}sin(x)=\frac{1sin^2(x)}{sin(x)}\)

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1With what you know in terms of trigonometric identities, you should be able to finish the job, can you not?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0csc(x)  sin(x) = 1?

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Anyway, from the identity \(sin^2(x)+cos^2(x)=1\) we conclude: \(1sin^2(x)=cos^2(x)\)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ohhhh...oops sorry... OHHH!!! I get it! yes that helps a lot!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thank you so much for your help/time!!

mathmate
 one year ago
Best ResponseYou've already chosen the best response.1Actually, looking back, you have been asked to "verify" the identity. What we did was to prove it. Verification means putting numbers on each side and show that the results are the same. You need to put different numbers, but make sure theta does not equal zero (because the expression becomes infinite, that's where the domain comes in). Sorry for having gone through long steps, but this will also prepare for your future topic on identities.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay thank you. I think I can do that... I have to go, but thank you again!

triciaal
 one year ago
Best ResponseYou've already chosen the best response.1sorry system was down @mathmate thank you
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