Show(1-tanx)/(1+tanx)^2 = cos2x?

At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.

Get our expert's

answer on brainly

SEE EXPERT ANSWER

Get your free account and access expert answers to this and thousands of other questions.

A community for students.

Show(1-tanx)/(1+tanx)^2 = cos2x?

Calculus1
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.

Get this expert

answer on brainly

SEE EXPERT ANSWER

Get your free account and access expert answers to this and thousands of other questions

is that cos^2(x) or cos(2x)
cos(2x)
okay start with the trig identiy for cos(2x)

Not the answer you are looking for?

Search for more explanations.

Ask your own question

Other answers:

http://prntscr.com/86l5g2 this one
turn tan in sin/cos and play around with it, tell me if u are still stuck
how to settle the(1+tanx)^2 i keep cant not get the answer cos2x
To me, it is not an identity. Counterexample Let test x = pi/6, the LHS = 0.1698729811 while the RHS =0.5
can do full step to me? i realy no idea==
to convert (1-tanx)/(1+tanx)^2 to cos2x
try to simplify (1+tanx)^2 to (sec^2x+2tanx) sec^2x+2sinx/cosx
do like dan suggested transfer tan to sin/cos that will be helpful
if it is (1-tan^2x)/(1+tan^2x)^2
?
hmm no i was talking about the denominator of left hand side (1+tanx)^2
manupilate that a bit more into sin and cos
then after that do the same with top too
but there is the square2 there confusing me
the square you need to distribute like you do with (a+b)^2
is(1+tan^4x) equal to sec^4x?
no
there is no such identity we have 1+tan^2x=sec^2x
let me start a bit \(\huge \frac{1-\tan x}{\sec^2x +2\frac{\sin x}{\cos x}}=\frac{\frac{\cos x-\sin x}{\cos x}}{\frac{1}{\cos^2x}+2\frac{\sin x}{\cos x }}\)
see if you can finish it off
you can cancel that cos that is in top and bottom
|dw:1440019023761:dw|
|dw:1440019515190:dw|
damn why did post the wrong question lol
i was wondering why your talking about 1-tan^2x in a reply so that was the question
haha sorry but i still learn to u
well you had us work the wrong thing all the way hhh but no worries
work the other way around from cos2x
|dw:1440019749527:dw|
cos2x=cos^2x-sin^2x
factor cos^2x to get cos^2x(1-tan^2x)
that's one step
recall that cos^2x=1/sec^2x
but again you sure it is (1+tan^2x)^2? make sure
should be only 1+tan^2x
hh ya realy sure
i need to proven the answer is cos2x
|dw:1440020130101:dw|
yup
i got 1-tan^2x/1+tan^2x=cos^2 not square the bottom
it cannot be right the way you wrote it please make sure post the picture yo getting u all confused now hhhh
but still can get the answer as cos2x jz dono the way how to do
no it can't if my result is correct that cannot be true
unless you have a different question
the last picture you post is my question
screenshot, or url
if i had a penny....
please screenshot that thing man we got confused now
|dw:1440020383353:dw| if you are talking about this the question is wrong not an identity
ya this is my question as exam
does it say to disprove or to prove?
or does it just say to show?
well depends on what the question really states perhaps it want to you see whether that is an identity or not
so to answer this it is not true not an identity
|dw:1440020646681:dw|
if like this?
look if it is not an identity no matter what you try you won't get there haha
so sad
|dw:1440020700278:dw|
lrisboy 123 i think there is no number inn answer because cos2x is the answer jz need to prove it (1-tan^2x)/(1+tan^2x)^2 equal to cos2x
there should be *every * number in answer, if it was true. yes? x = 0 works. !!
but 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
thanks @freckles
if you meant \[\frac{1-\tan^2(x)}{1+\tan^2(x)}=\cos(2x) \] we would have had more luck
because this is a true equation
on the left hand side's domain of course
\(\dfrac{1-tan^2(x)}{(1+tan^2(x))^2}\\=\dfrac{1-tan^2(x)}{sec^4(x) }\\= \dfrac{1}{sec^4x}-\dfrac{tan^2x}{sec^4x}\\= cos^4x-cos^2xsin^2x\\=cos^2(x)(cos^2(x)-sin^2(x) )= cos^2(x) (cos(2x))\) No way for you to get cos (2x) only.

Not the answer you are looking for?

Search for more explanations.

Ask your own question