Question about where to start this trig substitution integral

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SUMMARY

The integral ∫ x²√(a² - x²) dx from 0 to a can be evaluated using the substitution x = a sin(θ). This substitution transforms the integral into a more manageable form. The bounds of the integral change accordingly: when x = 0, θ = 0, and when x = a, θ = π/2. This method simplifies the evaluation of the integral significantly.

PREREQUISITES
  • Understanding of trigonometric substitutions in calculus
  • Familiarity with integral calculus techniques
  • Knowledge of the arcsine function and its properties
  • Ability to manipulate integral bounds during substitutions
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  • Study the method of trigonometric substitution in integral calculus
  • Learn how to change the bounds of integrals after substitution
  • Practice evaluating integrals involving square roots and polynomial expressions
  • Explore additional examples of integrals using the substitution x = a sin(θ)
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Students studying calculus, particularly those focusing on integral techniques and trigonometric substitutions, will benefit from this discussion.

vande060
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Homework Statement



∫ x^2√(a^2 - x^2) dx evaluate integral from 0 to a







Homework Equations





The Attempt at a Solution



so i know the format of this problem requires the substitution of asinϑ -π/2 ≤ ϑ ≤ π/2 , but i don't know how to change the bounds of the integral after the substitution of ϑ. i just nedd help with this point the rest of the problem shouldn't be an issue
 
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You're substituting x = a sin (t) so plug your limits into x then solve for t.
Ex:
0 = a sin(t) -> 0 = sin(t) -> arcsin(0) = t -> t = 0.

for upper boundary plug in x = a you get:

a = a sin(t) -> 1 = sin(t) -> arcsin(1) = t -> pi/2
 

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