Change to polars double integral

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SUMMARY

The discussion focuses on converting Cartesian coordinates to polar coordinates for double integrals, specifically addressing the transformation of variables in the context of a homework problem. The user successfully identifies that the inner integral results in r^5 when converting to polar coordinates using the equations x = r cos θ and y = r sin θ. The main challenge lies in determining the appropriate ranges for r and θ based on the given Cartesian limits, particularly for the integration region defined by y = 0 to y = √(1 - x²) and x = 0 to x = 1.

PREREQUISITES
  • Understanding of double integrals in calculus
  • Familiarity with polar coordinate transformations
  • Knowledge of Cartesian coordinate systems
  • Ability to sketch regions of integration in the x,y plane
NEXT STEPS
  • Study the process of converting Cartesian coordinates to polar coordinates in double integrals
  • Learn how to derive integration limits for polar coordinates from Cartesian equations
  • Explore graphical methods for sketching regions of integration
  • Practice solving double integrals with varying limits in polar coordinates
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Students studying calculus, particularly those focusing on double integrals and coordinate transformations, as well as educators seeking to enhance their teaching methods in these topics.

Kuma
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Homework Statement



Here is the question

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Homework Equations


The Attempt at a Solution



So converting to polars by x = r cos θ, y = r sin θ gives me r^5 in the inner integral

but how do you convert the ranges?

y goes from 0 to sqrt 1 - x^2, so that is just r, I could tell just by looking at it, but in a harder question how do you derive the range in terms of r? x goes from 0 to 1, but how do you convert that in terms of θ (an angle)?
 
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Have you sketched the region of integration?
 
Draw the domain of integration in the x,y plane (like in the figure) and find the ranges of θ and r from there.

ehild
 

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