Recent content by erba

You could consider the geophysical offshore industry. Sure, the oil industry is not that strong at this moment, but the renewable energy sector is doing better. So there are vacancies from time to time. It still involves quite a lot of computer work, but you for sure get to travel to remote...

Regarding a weakness of paleomagnetism think in terms of plate tectonics and how that affects the oceanic crust.

Thanks for the help! Guess I should re-think even the, relatively, more trivial steps more often.

Tanks for the sign error. And I realized that I was a bit unclear in my previous post. Solving the integral gives me: $$-sin(2t) + 2sin(t) + 4t$$ Plugging that into the equation that we were supposed to solve gives $$y(t) + \int_{0}^{t} (t-u)y(u)\,du = 3sin(2t)$$ $$4sin(2t) - 2sin(t) +...

Thanks for the help! I should use y(u) as I try to solve the integral, which I now realize depends on u and not t, right? If I would have tried to solve the convolution then y(t) would have been the right choice? Well, when I try to solve 4\sin 2t - 2\sin t + \int_0^t (t-u)(4\sin 2u - 2\sin...

Homework Statement Solve the integral y(t) + \int_0^t (t-u)y(u) \, du = 3sin(2t) Homework EquationsThe Attempt at a Solution Rewrite the equation: y(t) = 3sin(2t) - \int_0^t (t-u)y(u) \, du I assume the integral to be the convolution: f(t) * y(t) = t * y(t) as f(t-u) = f(t) = t...

Nevermind, just realized what I did wrong. I did put -1^n instead of (-1)^n into my calculator.

I saw somewhere that an alternate form of cos(n×π) was cos(n×π) = -1n+1 But to me this does not make sense. Am I wrong? For n = 0 cos(n×π) = 1 -1n+1 = -1 For n = 1 cos(n×π) = -1 -1n+1 = 1 etc. Is there another way to express cos(n×π) in an alternate form? PS. This is related to Fourier series.

We have a wave ψ(x,z,t). At t = 0 we can assume the wave to have the solution (and shape) ψ = Q*exp[-i(kx)] where k = wavenumber, i = complex number The property for a Fourier transform of a time shift (t-τ) is FT[f(t-τ)] = f(ω)*exp[-i(ωτ)] Now, assume ψ(x,z,t) is shifted in time...