Computing Int. sqrt(1-cost) | Just an Integral

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Homework Help Overview

The discussion revolves around computing the integral of the expression involving the square root of \(1 - \cos(t)\). The subject area is integral calculus, specifically focusing on trigonometric integrals.

Discussion Character

  • Exploratory, Mathematical reasoning

Approaches and Questions Raised

  • Participants explore the relationship between the integral and half-angle formulas, with one suggesting the use of the identity \(\sin(t/2) = \pm \sqrt{\frac{1 - \cos(t)}{2}}\). Another participant attempts to manipulate the expression into a different form involving \(u\)-substitution.

Discussion Status

The discussion includes various approaches to the integral, with one participant providing a detailed manipulation of the expression. While there is an expression of gratitude for the contributions, no explicit consensus or final solution has been reached.

Contextual Notes

Participants are navigating through trigonometric identities and substitutions, with some uncertainty regarding the implications of the plus or minus in the half-angle formula. The discussion reflects the complexities involved in integrating trigonometric functions.

quasar987
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How could I compute

[tex]\int \sqrt{1-cost} \ \ dt[/tex]

?
 
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just throwing this out there... could it have anything to do with a hanfle angle formula??

because i do rmember that
[tex]\sin t/2 = \pm \sqrt{\frac{1 - \cos (t)}{2}}[/tex]

that plus or minus does make things a bit... iffy though
 
Sqrt ( 1- cost)
Sqrt ( 1 - cos^2t) / Sqrt (1 + Cost)
Sqrt ( Sin^2t) / Sqrt (1 + Cost)
Sint / Sqrt (1 + Cost)
Integral becomes: I = Int ( sint/ sqrt( 1+ Cost) ) dt
Let u = 1 + Cost
du/dt= -Sint
du = -Sintdt
Integral becomes: I = -Int ( -du/Sqrt (u) )
I = -2 Sqrt(u) + C
I = -2 Sqrt (1 + Cost) + C
 
Excellent! Thanks you very much acm!
 

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