Recent content by Irene Kaminkowa

  1. Irene Kaminkowa

    A Analytical Integration of a Difficult Function

    Sure, since the expression under the root becomes negative
  2. Irene Kaminkowa

    Electric Field Energy Density: Plates of Q & A

    My answer is 5.085⋅105 J/m3? Regards to your teacher )
  3. Irene Kaminkowa

    Electric Field Energy Density: Plates of Q & A

    But have it in your mind. Derive the final formula.
  4. Irene Kaminkowa

    Electric Field Energy Density: Plates of Q & A

    Energy density is ω = W / V = E / (Ad) where W - energy, V - volume, d - distance between the plates. Capacity of the system (actually, we consider a capacitor) C = ε0A/d Energy W = Q2/2С Hope, it is enough to find the solution.
  5. Irene Kaminkowa

    Electric Field Energy Density: Plates of Q & A

    What is the distance between plates?
  6. Irene Kaminkowa

    Finding All Pairs of Positive Integers for (22016+ 5)m + 22015 = 2n + 1

    Speaking about ends 22016 ends with 6 22015 ends with 8 Thus (22016 + 5)m + 22015 ends with 9 n = 4k + 3
  7. Irene Kaminkowa

    Efficient Integration of Trigonometric Functions: Solving ∫ (1/sin 2x)dx

    Another way $$ \int \frac{dx}{sin(2x)} = \int \frac{dx}{2sinx~cosx} = \int \frac{dx}{2cos^2 x~tanx} = \begin{bmatrix} t = tan x\\ dt = \frac{dx}{cos^2x} \end{bmatrix} = \frac{1}{2}\int \frac{dt}{t}= \frac{1}{2}ln|t| + C = \frac{1}{2}ln|tan x| + C $$
  8. Irene Kaminkowa

    Why Are The Units of Coulombs Law What They Are?

    Actually, it is: https://en.wikipedia.org/wiki/Inverse-square_law
  9. Irene Kaminkowa

    MATLAB How to Calculate the Second Derivative of a Curve in Matlab?

    anahita, you can siply use finite differencies: https://en.wikipedia.org/wiki/Finite_difference
  10. Irene Kaminkowa

    Are Holodecks Possible in the Future of Star Trek?

    Data failed to replicate himself in his daughter, who became "unstable". His brother was an "evil twin", kind of "unstable" either. Thus, humans are the only rational choice. Not being too smart, you won't be too dangerous )
  11. Irene Kaminkowa

    A Can this optimization problem be solved?

    If N is not too big, you can find "brute force" numerical solution. The code is simple. No "conventional solver" is needed. Or, you can find Cij and then feed any solver with them.
  12. Irene Kaminkowa

    Quadratic discriminant with tricky algebra

    In the second equation there is a misprint The correct equation is (a+c-b)x2-2(a-c)x+(a+c+b) = 0 The proof is not difficult. Just find the discriminant.
  13. Irene Kaminkowa

    Dynamic Arrays (One, two, three dimensions)

    According to the sacred book ;) dereferenced pointers are recommended instead of array substript, that is *(*(*(A + i) + j)+k) instead of A [i ][j ][k ] As for transformation of a 3D array into 1D, the rule is simple Assume d1,d2,d3 - dimensions Then A[i ][j ][k ] = A_line [k + d3⋅(j + d2⋅i)]
  14. Irene Kaminkowa

    Solving a differential equation using integrating factor

    Another approach dy/dx = 2x(y+1) dy/(y+1) = 2xdx y+1 = Cex2
  15. Irene Kaminkowa

    C: remove recursively elements of a list

    Is remLista for removal? Then, look at your pushBack. When do you use malloc? Free is the symmetric operation: you are to deallocate your node. Here you can find the thorough instructions both for recursive and iterative implementation: https://www.cs.bu.edu/teaching/c/linked-list/delete/
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