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If uu(x,y)=x2+y2x+y, prove that vuux∂v∂x+y∂u∂y=32u - Mathematics

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प्रश्न

If `"u"(x , y) = (x^2 + y^2)/sqrt(x + y)`, prove that `x (del"v")/(delx) + y (del"u")/(dely) = 3/2 "u"`

योग

उत्तर

`"u"(x , y) = (x^2 + y^2)/sqrt(x + y)`

`"u"(lambdax , lambday) = (lambda^2x^2 + lambda^2y^2)/sqrt(lambdax + lambday)`

= `(lambda^2(x^2 + y^2))/(lambda^(1/2) sqrt(x + y))`

= `(lambda^(1/2) (x^2 + y^2))/sqrt(x + y)`

u is a homogeneous function of degree `3/2`

By Euler's Theorem,

`x (del"v")/(delx) + y (del"u")/(dely) = 3/2 "u"`

shaalaa.com
Linear Approximation and Differential of a Function of Several Variables
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 8: Differentials and Partial Derivatives - Exercise 8.7 [पृष्ठ ८६]

APPEARS IN

सामाचीर कलवी Mathematics - Volume 1 and 2 [English] Class 12 TN Board
अध्याय 8 Differentials and Partial Derivatives
Exercise 8.7 | Q 4 | पृष्ठ ८६

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