Verify that this an identity: (sec x - tan x)^2 + 1 all over sec x*csc x - tan x*csc x is equal to 2 tan x.
???
\[\huge \frac{(sec x - \tan x)^2 + 1}{\sec x \csc x - \tan x \csc x} \equiv 2\tan x\] yes?
Yep! I keep getting really complicated fractions on the left side (obviously I would work on that side), can u guide me to 2tan x?
show me what you have
Um I wouldnt mind at all, nut it's kind of hard to type all of it on the iPod. My last line was (2 tan x sec x)/(sec x csc x - sec ). The denominator is what Is really screwing everything up, is there a way to simplify it?
*but, iPad
ahh i see it now. (i'll assume what you have done so far is right) you have \[\huge \frac{2 \tan x \sec x}{\sec x \csc x - \sec x}\] can you see that sec x is factorable in the denominator?
hmm now that i think about it... the numerator might be wrong...let me try solving it
Oh wait that's only half of it! That is the fraction being subtracted from (2 sec^2 x)/(sec x csc x - sec x)! Lol
ahh so you really have \[\Large \frac{2\sec^2 x}{\sec x \csc x - \sec x} - \frac{2\tan x}{\sec x \csc x - \sec x}\] yes?
Yeah. I separated the fraction, but I don't think that's going to get me anywhere
* 2 tan x sec x
In the second frac
like i said...the sec x is factorable \[\Large \implies \frac{2\sec^2 x}{\sec x(\csc x - 1)} - \frac{2 \tan x\sec x}{\sec x (\csc x - 1)}\] yes?
Yes I saw that as well , but I erased it. Oh I see now that it can simplify the expression
indeed. so do you know the rest?
Well now it's down to 2sec x/ (csc x-1) - 2tan x/(csc x-1) I would guess you would make tan x sin x over cos x, but what about the denominator?
good question \[\csc x - 1\] \[\implies \frac 1{\sin x} - \frac{\sin x}{\sin x}\] \[\implies \frac{1 - \sin x}{\sin x}\]
Ok I'm down to 2sec x /(csc x -1) -2 sec x -2 tan x sin x, I'll get rid of denom
Thanks for the help, btw !You're really helpful :)
welcome
Ok im fraction free now, but what I have doesn't resemble 2tan x at all.... I have 2 sec x csc x - 4 sec x - 2 tan x sin x
\[\frac{2\sec x}{\csc x -1} - \frac{2\tan x}{\csc x - 1}\] \[\implies \frac{\frac 2{\cos x}}{\frac{1-\sin x}{\sin x}} - \frac{\frac{2\sin x}{\cos x}}{\frac{1-\sin x}{\sin x}}\] \[\frac{2\tan x}{1 - \sin x} - \frac{2\tan x \sin x}{1-\sin x}\] is that what you did?
Yes! After that, you just bring the fractions together, factor out the 2 tan x, and the 1- sin x cancels out! Woohoo I got it! Thank you so much 4 ur help!
welcome
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