Recent content by Erbil

  1. E

    Euler - Lagrange Equation(changing variable)

    Before that,I would like to ask can I use the method what I've linked for solve these problems?
  2. E

    Euler - Lagrange Equation(changing variable)

    I think it will be ; $$F(y, x, x') = (1+x'^2)/x' ^\frac12 y^\frac32 $$
  3. E

    Euler - Lagrange Equation(changing variable)

    http://math.stackexchange.com/questions/407791/eulerlagrange-equation-changing-variable/415427#415427 He is saying that changing the variables in this situation is immaterial.
  4. E

    As a physicist, should I boder about mathematics proofs/demonstrations

    I think Applied Mathematics is enough.Take a look at here : http://www.staff.science.uu.nl/~hooft101/theorist.html
  5. E

    How Can I Self-Study Math and Physics?

    you can start from here : http://www.intmath.com/ + https://www.coursera.org/course/phys1
  6. E

    Euler - Lagrange Equation(changing variable)

    Create the Euler-Lagrange equation for the following questions (if it's necessary change the variables). Homework Statement $$\tag{1}\int _{y_{1}}^{y2}\dfrac {x^{'}{2}} {\sqrt {x^{'}{2}+x^{2}}}dy$$ $$\tag{2}\int _{x_{1}}^{x_{2}}y^{3/2}ds $$ $$\tag{3} \int \dfrac {y.y'} {1+yy{'}}dx...
  7. E

    Vector Operations: Solving Gradient, Divergence, Curl and Laplacian Problems

    OK.Here is my expression. = (18z^2-12+72x+2z-6z^2+2y-6yz) + ( 24-4z-3z^2-8y+2x-6xz) + (36xz+36x^2-9z^2-4y+2x-12xz-6yz-6xy) = 36x^2-6xy-12yz+6y+18xz am I right?
  8. E

    Vector Operations: Solving Gradient, Divergence, Curl and Laplacian Problems

    @mfb; Is there any another way,because there are a lot of process with step by step? Now,I'm trying step by step.I will tell the result,but I don't know where can I control it?
  9. E

    Vector Operations: Solving Gradient, Divergence, Curl and Laplacian Problems

    Homework Statement $$ \overrightarrow {F}=3xz^{2}i+2xyj-x^{2}k $$ $$\phi =3x^{2}-yz $$ are given vector and scalar fields, respectively. a) $$\quad \operatorname{div}\left( \operatorname{grad}\phi \operatorname{div}\overrightarrow {F}\right) =\quad? $$ b) $$\quad...
  10. E

    Solving the Gamma Function: Using Recursion & Tables

    Oh what I was did.it will be u^1/3 =? Not yet.But I will.
  11. E

    Solving the Gamma Function: Using Recursion & Tables

    Can I use same logic for 12? x^3 = u 3x^2dx= du dx = du / 3*√u ∫xe^-x^3 = ∫u^1/3*e^-u du/3*√u= 1/3 ∫ u^-1/6 e^-udu = 1/3 * Gamma -5/6 ...?+ No idea for 15?
  12. E

    Solving the Gamma Function: Using Recursion & Tables

    Thanks!
  13. E

    Solving the Gamma Function: Using Recursion & Tables

    I understand but what about dx ? Would be? x^2=u 2xdx = du dx = du/2x (I'm asking about this x?) $$ \int _{0}^{\infty }ue^{-u}? $$
  14. E

    Solving the Gamma Function: Using Recursion & Tables

    Yes.There's a problem.But I can't figure. if we say u=x^2 --> 2xdx=du --> dx = du/2x Where to go from here? I can't remember how can I escape from x variable?
  15. E

    Solving the Gamma Function: Using Recursion & Tables

    5. 1/0.7(Gamma1.7) = 1.30 ? Isn't it? I'm sorry questions mess up.It's solution of question 11. Here is for (8) For n= 2/3 Gamma(n+1) = Gamma(1+2/3)=Gamma(1.6) = 0.89