Question

1/ tanx + cosx = tanx = sinx
prove the identity

Answer 1

got a typo there...

Answer 2

1/ tanx + cosx = tanx + sinx
maybe?

Answer 3

yeah sorry

Answer 4

its 1/ tanx + cosx = tanx + sinx

Answer 5

it's not true...
http://www.wolframalpha.com/input/?i=1%2Ftanx%2Bcosx%3Dtanx%2Bsinx
it's not an identity...

Answer 6

yeah it's not true, check your question again

Answer 7

how is it not an identity?
thats the right answer apparently

Answer 8

ash can u answer my question above this post

Answer 9

this question? it's a wrong identity

Answer 10

the one that says 13 minutes ago

Answer 11

where is it?

Answer 12

below your first post in this question

Answer 13

OK, i checked it, there must be an error
to prove
1/tan x+ cos x= sin x+tanx

Answer 14

how is it not an identity?
thats the right answer apparently

Answer 15

1/tan x+ cos x* tan x / tan x
(1+sin x)/ tan x
this is the end
we can also prove this wrong by replacing x with a value
say x=pi/6
sin pi/6= 1/2
cos pi/6=root 3/2
tan pi/6= 1/root 3
LHS we have \[1/\tan (\pi/6)+ \cos \pi/6\]
\[\sqrt 3+ \sqrt 3/2\]

RHS we have tan pi/6 + sin pi/6
\[1/ \sqrt 3+ 1./2\]
so LHS is not equal to RHS, this identity is not valid

Answer 16

ok thanks