Recent content by jakobsandberg

  1. J

    Differential Equations, Frobenius' Method

    Homework Statement Find the indicial roots of the following Differential Equation: xy'' - y' + x3y = 0 Homework Equations y = Ʃ[n=0 to infinity]cnxn+r y' = Ʃ[n=0 to infinity](n+r)cnxn+r-1 y'' = Ʃ[n=0 to infinity](r+r)(n+r-1)cnxn+r-2 The Attempt at a Solution Plugging these values into the...
  2. J

    Find the equivalent resistance in a circuit

    So this would leave me with two parallel resistors of 8 Ohms each? And finding the equivalent resistance would give us 4 Ohms? If you (or someone else) can confirm this, it would be greatly appreciated!
  3. J

    Calculating Wavelength and Understanding Sound Interference in a Room

    The first part is correct. The second part sounds correct, though I am not positive. EDIT: Actually, there would not be a change in frequency. You would hear the sound sooner, but the frequency (and wavelength) would remain the same.
  4. J

    Find the equivalent resistance in a circuit

    Homework Statement Find the equivalent resistance in the circuit below: Homework Equations The Attempt at a Solution I know the two 4 Ohm resistors (on the same wire) are in series and thus add to 8 Ohms. However, I do not know where to go from here. When the resistors are in a...