39anchal , your first steo itself is wrong
u have wriiten cotx logx
it should be cotx logy
4 Answers
1takin log both sides,
cotx logx + y(logtan-1x) = 0
diffrentiating with respect to x,
-cosec2x.logx+1/x.cotx + dy/dx(1/tan-1x.1/1+x2)=0
cosec2x.logx - cotx/x = dy/dx(1/tan-1x.(1+x2))
dy/dx=tan-1x(1+x2)(cosec2x.logx - cotx/x)
391oops..sry that's a mistake..
bt the main thing is we hav to take log,
nd rest is simple...
sry for this mistake...
39yup your method was very much correct.
no need for sorry , but never hurry like this in a exam....
