Math Problem Statement
Consider the transformation from Cartesian coordinates $(x,y)$ to parametric $(u,v)$ defined by the following: x = u³-3uv² y = 3u-v-v3 Calculate the Jacobian determinent $ J = \frac{\partial(x,y)}{\partial(u,v)) $, then evaluate the double integral over the region $D$ in the $uv$ plane definite by $u^2 + v^2 = 1$: 1= f (x²+y²) du dv D
Solution
Step 1: Calculate the Jacobian Determinant
Given the transformation: the Jacobian matrix is:
\begin{pmatrix} \frac{\partial x}{\partial u} & \frac{\partial x}{\partial v} \\ \frac{\partial y}{\partial u} & \frac{\partial y}{\partial v} \end{pmatrix}.$$ #### Compute the partial derivatives: 1. **Partial derivatives of $$x$$:** $$\frac{\partial x}{\partial u} = \frac{\partial}{\partial u}(u^3 - 3uv^2) = 3u^2 - 3v^2,$$ $$\frac{\partial x}{\partial v} = \frac{\partial}{\partial v}(u^3 - 3uv^2) = -6uv.$$ 2. **Partial derivatives of $$y$$:** $$\frac{\partial y}{\partial u} = \frac{\partial}{\partial u}(3u - v - v^3) = 3,$$ $$\frac{\partial y}{\partial v} = \frac{\partial}{\partial v}(3u - v - v^3) = -1 - 3v^2.$$ Thus, the **Jacobian matrix** is: $$J = \begin{pmatrix} 3u^2 - 3v^2 & -6uv \\ 3 & -1 - 3v^2 \end{pmatrix}.$$ #### Calculate the Jacobian Determinant: $$\det(J) = (3u^2 - 3v^2)(-1 - 3v^2) - (-6uv)(3).$$ Expanding: $$\det(J) = -3u^2 - 9u^2v^2 + 3v^2 + 9v^4 + 18uv = 3v^2 - 3u^2 + 9v^4 - 9u^2v^2 + 18uv.$$ --- ### Step 2: Set Up the Double Integral The integral is: $$\iint_D f(x^2 + y^2) \, du \, dv,$$ where $$D$$ is the region defined by $$u^2 + v^2 = 1$$. ---Ask a new question for Free
By Image
Drop file here or Click Here to upload
Math Problem Analysis
Mathematical Concepts
Multivariable Calculus
Jacobian Determinant
Double Integrals
Coordinate Transformations
Formulas
Jacobian Matrix: J = [∂x/∂u ∂x/∂v; ∂y/∂u ∂y/∂v]
Jacobian Determinant: det(J) = (∂x/∂u)(∂y/∂v) - (∂x/∂v)(∂y/∂u)
Double Integral: ∫∫_D f(x² + y²) du dv
Theorems
Change of Variables Theorem
Jacobian Determinant for Coordinate Transformations
Suitable Grade Level
Undergraduate
Related Recommendation
Jacobian Calculation and Integral Transformation for Elliptical Region
Evaluating Double Integral with Transformation in Calculus
Change of Variables in Double Integration: Ellipse and Region Enclosed by Curves
Convert Double Integral to Polar Coordinates and Evaluate: Step-by-Step Solution
Advanced Double Integral Problem: Change of Variables and Jacobian Determinant