Recent content by physicsnewb7

every fourth derivative gives you sin(x) I think you can take it from there

I think they mean take the 39th derivative of sin(x) and evaluate that at pi/2 the 2nd derivative -sin(x) third is -cos(x) and fourth is sin(x)...

I agree. The history channel once upon a time fell in the 0.1% but now...ancient aliens and swamp people lol. The only documentaries I trust now are on science channel.

It's mentioned in the documentary about tesla on the history channel. The name of the documentary is "The History Channel-Modern Marvels:Nikola Tesla:Mad Electricity." Mind you they also air ancient aliens so much its as if they believe aliens were apart of everyday life in antiquity.

Homework Statement find the laurent series of sin(2z)/(z^3) in [z]>0 Homework Equations The Attempt at a Solution I am completely confused. I can understand some of the examples given on laurent series, like using partial fractions and then finding geometric series. Do I rewrite...

ohhhhh nevermind i finally got it you rewrite the denominator as (z+i)(z-i) then do the partial fraction. so simple! you were right rizardonthanks

So I do the partial fraction after i expand out? expanding (z+i)/(z^2+1) I get (x+yi+i)/(x^2+2xyi-y^2+1) how am I supposed to factor the denominator?

all i want is a simple hint i don't want anyone to do the problem for me I just want a little help. just a little push in the right direction would be so helpful.

Homework Statement write f(z)= (z+i)/(z^2+1) in the form w=u(x,y)+iv(x,y) Homework Equations The Attempt at a Solution I tried using the conjugate and also expanding out algebraically but I can not seem to get the right answer. I know what the answer is...

it turns out that that individual spilt something on it. he just confessed, so a new keyboard it is...

which one?

Homework Statement s2/((s2-1)(s-1)2) Homework Equations laplace tables The Attempt at a Solution I attempted the shifting method and also partial fraction method but efforts were fruitless

Someone hit some random combination of keys that locked up some of the keyboard. A few of them started working but there is still a couple that don't work. Does anyone know how to unlock these keys?:rolleyes:

Thank you very much you have been very helpful. I appreciate it

oh yeah i know i put cos by accident, but that is the solution right? I arrived at this solution by a long trial and error method. any way to quickly get at it in general?