Integration using separation of parts

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SUMMARY

The discussion focuses on evaluating the integral of cos-1(2x) dx using integration by parts. The correct approach involves setting u = cos-1(2x) and dv = dx, leading to the derivative du = -2/(sqrt(1 - (2x)2)) dx. The integration by parts formula is applied, resulting in the expression u * v - ∫v du, where v is the integral of dx. The participants clarify that the initial misunderstanding involved incorrectly multiplying arccos by 2x.

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  • Understanding of integration by parts
  • Familiarity with inverse trigonometric functions, specifically arccos
  • Knowledge of differentiation and integration techniques
  • Ability to manipulate square roots and algebraic expressions
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  • Study the integration by parts formula in detail
  • Learn about the properties of inverse trigonometric functions
  • Practice solving integrals involving composite functions
  • Explore advanced techniques for integrating functions with square roots
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Students studying calculus, particularly those focusing on integration techniques, as well as educators looking for examples of integration by parts involving inverse functions.

crazco
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Homework Statement



evaluate the integral cos^-1 2x dx?


Homework Equations





The Attempt at a Solution



let

u = arc cos
du = -1 / (sqrt 1-x^2)
dv = 2x
v= x^2

arc cos * x^2 - the integral of -x^2 / (sqrt 1-x^2)

then i don't know what to do
 
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crazco said:

The Attempt at a Solution



let

u = arc cos
du = -1 / (sqrt 1-x^2)
dv = 2x
v= x^2

arc cos * x^2 - the integral of -x^2 / (sqrt 1-x^2)

then i don't know what to do

What you have is ∫cos-1(2x) dx

so u = cos-1(2x) and dv=dx
 
This is NOT "arccos" multiplied by 2x!
 

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