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anonymous
 one year ago
Show(1tanx)/(1+tanx)^2 = cos2x?
anonymous
 one year ago
Show(1tanx)/(1+tanx)^2 = cos2x?

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0is that cos^2(x) or cos(2x)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay start with the trig identiy for cos(2x)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0http://prntscr.com/86l5g2 this one

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0turn tan in sin/cos and play around with it, tell me if u are still stuck

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0how to settle the(1+tanx)^2 i keep cant not get the answer cos2x

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0To me, it is not an identity. Counterexample Let test x = pi/6, the LHS = 0.1698729811 while the RHS =0.5

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0can do full step to me? i realy no idea==

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0to convert (1tanx)/(1+tanx)^2 to cos2x

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2try to simplify (1+tanx)^2 to (sec^2x+2tanx) sec^2x+2sinx/cosx

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2do like dan suggested transfer tan to sin/cos that will be helpful

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0if it is (1tan^2x)/(1+tan^2x)^2

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2hmm no i was talking about the denominator of left hand side (1+tanx)^2

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2manupilate that a bit more into sin and cos

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2then after that do the same with top too

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0but there is the square2 there confusing me

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2the square you need to distribute like you do with (a+b)^2

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0is(1+tan^4x) equal to sec^4x?

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2there is no such identity we have 1+tan^2x=sec^2x

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2let me start a bit \(\huge \frac{1\tan x}{\sec^2x +2\frac{\sin x}{\cos x}}=\frac{\frac{\cos x\sin x}{\cos x}}{\frac{1}{\cos^2x}+2\frac{\sin x}{\cos x }}\)

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2see if you can finish it off

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2you can cancel that cos that is in top and bottom

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.0dw:1440019023761:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1440019515190:dw

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2damn why did post the wrong question lol

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2i was wondering why your talking about 1tan^2x in a reply so that was the question

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0haha sorry but i still learn to u

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2well you had us work the wrong thing all the way hhh but no worries

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2work the other way around from cos2x

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.0dw:1440019749527:dw

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2cos2x=cos^2xsin^2x

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2factor cos^2x to get cos^2x(1tan^2x)

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2that's one step

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2recall that cos^2x=1/sec^2x

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2but again you sure it is (1+tan^2x)^2? make sure

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2should be only 1+tan^2x

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i need to proven the answer is cos2x

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2dw:1440020130101:dw

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2i got 1tan^2x/1+tan^2x=cos^2 not square the bottom

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2it cannot be right the way you wrote it please make sure post the picture yo getting u all confused now hhhh

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0but still can get the answer as cos2x jz dono the way how to do

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2no it can't if my result is correct that cannot be true

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2unless you have a different question

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0the last picture you post is my question

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.0screenshot, or url

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.0if i had a penny....

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2please screenshot that thing man we got confused now

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2dw:1440020383353:dw if you are talking about this the question is wrong not an identity

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ya this is my question as exam

freckles
 one year ago
Best ResponseYou've already chosen the best response.0does it say to disprove or to prove?

freckles
 one year ago
Best ResponseYou've already chosen the best response.0or does it just say to show?

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2well depends on what the question really states perhaps it want to you see whether that is an identity or not

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2so to answer this it is not true not an identity

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1440020646681:dw

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.2look if it is not an identity no matter what you try you won't get there haha

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.0dw:1440020700278:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0lrisboy 123 i think there is no number inn answer because cos2x is the answer jz need to prove it (1tan^2x)/(1+tan^2x)^2 equal to cos2x

IrishBoy123
 one year ago
Best ResponseYou've already chosen the best response.0there should be *every * number in answer, if it was true. yes? x = 0 works. !!

freckles
 one year ago
Best ResponseYou've already chosen the best response.0but they already said it cannot be proven because it is not an identity @IrishBoy123 was giving a counterexample aka proving it is a false equation

freckles
 one year ago
Best ResponseYou've already chosen the best response.0if you meant \[\frac{1\tan^2(x)}{1+\tan^2(x)}=\cos(2x) \] we would have had more luck

freckles
 one year ago
Best ResponseYou've already chosen the best response.0because this is a true equation

freckles
 one year ago
Best ResponseYou've already chosen the best response.0on the left hand side's domain of course

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\(\dfrac{1tan^2(x)}{(1+tan^2(x))^2}\\=\dfrac{1tan^2(x)}{sec^4(x) }\\= \dfrac{1}{sec^4x}\dfrac{tan^2x}{sec^4x}\\= cos^4xcos^2xsin^2x\\=cos^2(x)(cos^2(x)sin^2(x) )= cos^2(x) (cos(2x))\) No way for you to get cos (2x) only.
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