Can someone explain this inverse tan integral for me please?

Click For Summary
SUMMARY

The discussion focuses on evaluating the integral of (Ldv)/(AgL+v^2) from [v0,0] and deriving the arctan function from it. The key substitution involves using v = √(AgL)tanθ or v = x√(AgL), which simplifies the integral to a form that can be integrated to yield arctan. The transformation of the integral is achieved by dividing both the numerator and denominator by AgL, leading to a new variable u = v/√(AgL) and resulting in the integral √(L/Ag) ∫ (du)/(1+u^2).

PREREQUISITES
  • Understanding of integral calculus, specifically techniques for integration.
  • Familiarity with trigonometric substitutions in integrals.
  • Knowledge of the arctan function and its properties.
  • Basic algebraic manipulation skills for simplifying expressions.
NEXT STEPS
  • Study trigonometric substitution techniques in integral calculus.
  • Learn about the properties and applications of the arctan function.
  • Explore advanced integration techniques, including integration by parts and partial fractions.
  • Practice solving integrals involving rational functions and their transformations.
USEFUL FOR

Students and professionals in mathematics, physics, and engineering who are working with integrals and trigonometric functions, particularly those seeking to deepen their understanding of integration techniques.

btbam91
Messages
91
Reaction score
0
integral of
(Ldv)/(AgL+v^2) from [v0,0]

I'm supposed to get (...)arctan(...)

where (...) are 2 different quantities.
I'm confused on how to get arctan out of this integral whenarctan = integral of

(1*dv)/(1+v^2) from [0,x]

Help is appreciated.
 
Physics news on Phys.org
hi btbam91! :smile:

(try using the X2 icon just above the Reply box :wink:)

scale it down … substitute v = x√(AgL) :wink:

(or go straight to v = √(AgL)tanθ)
 
Equivalently, divide both numerator and denominator of
\frac{ L dv}{AgL+ v^2}
by AgL:
\frac{\frac{1}{Ag}dv}{1+ \frac{v^2}{AgL}}
and then make the substitution
u= \frac{v}{\sqrt{AgL}}
Because du= dv/\sqrt{AgL} that changes the integral to
\sqrt{\frac{L}{Ag}}\int \frac{du}{1+ u^2}
 
Thanks guys! I really appreciate it!
 

Similar threads

Replies
10
Views
2K
  • · Replies 22 ·
Replies
22
Views
3K
  • · Replies 1 ·
Replies
1
Views
10K
  • · Replies 16 ·
Replies
16
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 13 ·
Replies
13
Views
8K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
2
Views
1K