English

Find D Y D X in the Following Case ( X 2 + Y 2 ) 2 = X Y ? - Mathematics

Advertisements
Advertisements

Question

Find  \[\frac{dy}{dx}\] in the following case \[\left( x^2 + y^2 \right)^2 = xy\] ?

 

Sum

Solution

\[\text{We have, } \left( x^2 + y^2 \right) = xy\]

Differentiating with respect to x, we get,

\[\Rightarrow \frac{d}{dx}\left[ \left( x^2 + y^2 \right)^2 \right] = \frac{d}{dx}\left( xy \right)\]
\[ \Rightarrow 2\left( x^2 + y^2 \right)\frac{d}{dx}\left( x^2 + y^2 \right) = x\frac{d y}{d x} + y\frac{d}{dx}\left( x \right) \]
\[ \Rightarrow 2\left( x^2 + y^2 \right)\left( 2x + 2y\frac{d y}{d x} \right) = x\frac{d y}{d x} + y\left( 1 \right)\]
\[ \Rightarrow 4x\left( x^2 + y^2 \right) + 4y\left( x^2 + y^2 \right)\frac{d y}{d x} = x\frac{d y}{d x} + y\]
\[ \Rightarrow 4y\left( x^2 + y^2 \right)\frac{d y}{d x} - x\frac{d y}{d x} = y - 4x\left( x^2 + y^2 \right)\]
\[ \Rightarrow \frac{d y}{d x}\left[ 4y\left( x^2 + y^2 \right) - x \right] = y - 4x\left( x^2 + y^2 \right)\]
\[ \Rightarrow \frac{d y}{d x} = \frac{y - 4x\left( x^2 + y^2 \right)}{4y\left( x^2 + y^2 \right) - x}\]
\[ \Rightarrow \frac{d y}{d x} = \frac{4x\left( x^2 + y^2 \right) - y}{x - 4y\left( x^2 + y^2 \right)}\]

shaalaa.com
  Is there an error in this question or solution?
Chapter 11: Differentiation - Exercise 11.04 [Page 74]

APPEARS IN

RD Sharma Mathematics [English] Class 12
Chapter 11 Differentiation
Exercise 11.04 | Q 8 | Page 74

Video TutorialsVIEW ALL [1]

RELATED QUESTIONS

​Differentiate the following function from first principles \[e^\sqrt{\cot x}\] .


Differentiate tan 5x° ?


Differentiate \[e^\sqrt{\cot x}\] ?


Differentiate \[\frac{3 x^2 \sin x}{\sqrt{7 - x^2}}\] ?


Differentiate \[\left( \sin^{- 1} x^4 \right)^4\] ?


If \[y = \log \left\{ \sqrt{x - 1} - \sqrt{x + 1} \right\}\] ,show that \[\frac{dy}{dx} = \frac{- 1}{2\sqrt{x^2 - 1}}\] ?


If  \[y = \left( x - 1 \right) \log \left( x - 1 \right) - \left( x + 1 \right) \log \left( x + 1 \right)\] , prove that \[\frac{dy}{dc} = \log \left( \frac{x - 1}{1 + x} \right)\] ?


Differentiate \[\sin^{- 1} \left( 1 - 2 x^2 \right), 0 < x < 1\] ?


Differentiate 

\[\tan^{- 1} \left( \frac{\cos x + \sin x}{\cos x - \sin x} \right), \frac{\pi}{4} < x < \frac{\pi}{4}\] ?


Differentiate \[\sin^{- 1} \left( \frac{1}{\sqrt{1 + x^2}} \right)\] with respect to x.


If \[y \sqrt{1 - x^2} + x \sqrt{1 - y^2} = 1\] ,prove that \[\frac{dy}{dx} = - \sqrt{\frac{1 - y^2}{1 - x^2}}\] ?


If \[\tan^{- 1} \left( \frac{x^2 - y^2}{x^2 + y^2} \right) = a\] Prove that  \[\frac{dy}{dx} = \frac{x}{y}\frac{\left( 1 - \tan a \right)}{\left( 1 + \tan a \right)}\] ?


Differentiate \[x^{\sin x}\]  ?


Differentiate  \[\left( x^x \right) \sqrt{x}\] ?


Find \[\frac{dy}{dx}\]  \[y = x^x + \left( \sin x \right)^x\] ?


If \[\left( \cos x \right)^y = \left( \tan y \right)^x\] , prove that \[\frac{dy}{dx} = \frac{\log \tan y + y \tan x}{ \log \cos x - x \sec y \ cosec\ y }\] ?


If \[e^x + e^y = e^{x + y}\] , prove that

\[\frac{dy}{dx} + e^{y - x} = 0\] ?


If \[y = x \sin \left( a + y \right)\] , prove that \[\frac{dy}{dx} = \frac{\sin^2 \left( a + y \right)}{\sin \left( a + y \right) - y \cos \left( a + y \right)}\] ?

 


If \[xy \log \left( x + y \right) = 1\] , prove that  \[\frac{dy}{dx} = - \frac{y \left( x^2 y + x + y \right)}{x \left( x y^2 + x + y \right)}\] ?


If \[y = x \sin y\] , prove that  \[\frac{dy}{dx} = \frac{y}{x \left( 1 - x \cos y \right)}\] ?

 


\[\text{ If }\cos y = x\cos\left( a + y \right),\text{  where } \cos a \neq \pm 1, \text{ prove that } \frac{dy}{dx} = \frac{\cos^2 \left( a + y \right)}{\sin a}\] ?

\[\text{ If }y = x^{\tan x} + \sqrt{\frac{x^2 + 1}{2}}, \text{ find} \frac{dy}{dx}\] ?

 


If \[y = \left( \tan x \right)^{\left( \tan x \right)^{\left( \tan x \right)^{. . . \infty}}}\], prove that \[\frac{dy}{dx} = 2\ at\ x = \frac{\pi}{4}\] ?

 


If \[y = e^{x^{e^x}} + x^{e^{e^x}} + e^{x^{x^e}}\], prove that  \[\frac{dy}{dx} = e^{x^{e^x}} \cdot x^{e^x} \left\{ \frac{e^x}{x} + e^x \cdot \log x \right\}+ x^{e^{e^x}} \cdot e^{e^x} \left\{ \frac{1}{x} + e^x \cdot \log x \right\} + e^{x^{x^e}} x^{x^e} \cdot x^{e - 1} \left\{ x + e \log x \right\}\]

 


If \[y = \left( \cos x \right)^{\left( \cos x \right)^{\left( \cos x \right) . . . \infty}}\],prove that \[\frac{dy}{dx} = - \frac{y^2 \tan x}{\left( 1 - y \log \cos x \right)}\]?

 


Find \[\frac{dy}{dx}\],when \[x = a e^\theta \left( \sin \theta - \cos \theta \right), y = a e^\theta \left( \sin \theta + \cos \theta \right)\] ?


If  \[x = \frac{1 + \log t}{t^2}, y = \frac{3 + 2\log t}{t}, \text { find } \frac{dy}{dx}\] ?


\[\sin x = \frac{2t}{1 + t^2}, \tan y = \frac{2t}{1 - t^2}, \text { find }  \frac{dy}{dx}\] ?

If \[y = \tan^{- 1} \left( \frac{1 - x}{1 + x} \right), \text{ find} \frac{dy}{dx}\]  ?


If f (x) is an even function, then write whether `f' (x)` is even or odd ?


The derivative of the function \[\cot^{- 1} \left| \left( \cos 2 x \right)^{1/2} \right| \text{ at } x = \pi/6 \text{ is }\] ______ .


The derivative of \[\sec^{- 1} \left( \frac{1}{2 x^2 + 1} \right) \text { w . r . t }. \sqrt{1 + 3 x} \text { at } x = - 1/3\]


If \[\sin^{- 1} \left( \frac{x^2 - y^2}{x^2 + y^2} \right) = \text { log a then } \frac{dy}{dx}\] is equal to _____________ .


Find the second order derivatives of the following function e6x cos 3x  ?


If x = 2aty = at2, where a is a constant, then find \[\frac{d^2 y}{d x^2} \text { at }x = \frac{1}{2}\] ?


If \[y = 1 - x + \frac{x^2}{2!} - \frac{x^3}{3!} + \frac{x^4}{4!}\] .....to ∞, then write  \[\frac{d^2 y}{d x^2}\] in terms of y ?


Let f(x) be a polynomial. Then, the second order derivative of f(ex) is



If \[y = \log_e \left( \frac{x}{a + bx} \right)^x\] then x3 y2 =

 


If `x=a (cos t +t sint )and y= a(sint-cos t )`  Prove that `Sec^3 t/(at),0<t< pi/2` 


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×