logo

Ask Questions, Get Answers

 
X
 Search
Want to ask us a question? Click here
Browse Questions
Ad
0 votes

If $\log (x+y)=2xy$ then $y'(0)=$

$\begin{array}{1 1} 1 \\ -1 \\ 2 \\ 0 \end{array} $

Can you answer this question?
 
 

1 Answer

0 votes
$\log(x+y)=2xy$
$\Rightarrow \large\frac{(1+dy/dx)}{(x+y)}=$$2.(x.\large\frac{dy}{dx}$$+y)$
$\Rightarrow \large\frac{dy}{dx}=\frac{1-2xy-2y^2}{2x^2+2xy-1}$
$\Rightarrow y'(0)=\large\frac{1-2}{-1}$
$\Rightarrow 1$ as at $x=0$,$y=1$
Hence (a) is the correct option
answered Dec 30, 2013 by sreemathi.v
 

Related questions

Ask Question
student study plans
x
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App
...