- #1
FrogPad
- 810
- 0
Note:
It looks like the LaTeX interpreter is not working right now. So I'll try and use plaintext and make things look pretty.
To my problem:
My algebra skills are kind of weak, but I am trying to show the Laplace transform of cos(at) and I keep getting stuck at this one spot.
it is where
L{e^(i*a*t)} = 1/(s+i*a)
How do I get the complex part out of the bottom? My TI-89 will do it for me automatically... but I can't just turn the solution in like that :)
So the TI-89 says that:
(or if LaTeX starts working again)
[tex]
\frac{1}{s+ia}=\frac{s}{s^2+a^2}+\frac{a}{s^2+a^2}*i
[/tex]
So how the hell is my calc doing that?... partial fractions maybe? I dunno... and it is friggn' bugging me. Thanks in advance.
Sorry about the ascii art :)
It looks like the LaTeX interpreter is not working right now. So I'll try and use plaintext and make things look pretty.
To my problem:
My algebra skills are kind of weak, but I am trying to show the Laplace transform of cos(at) and I keep getting stuck at this one spot.
it is where
L{e^(i*a*t)} = 1/(s+i*a)
How do I get the complex part out of the bottom? My TI-89 will do it for me automatically... but I can't just turn the solution in like that :)
So the TI-89 says that:
Code:
1 s a
---- = --------- + --------- i
s+ia s^2+a^2 s^2+a^2
(or if LaTeX starts working again)
[tex]
\frac{1}{s+ia}=\frac{s}{s^2+a^2}+\frac{a}{s^2+a^2}*i
[/tex]
So how the hell is my calc doing that?... partial fractions maybe? I dunno... and it is friggn' bugging me. Thanks in advance.
Sorry about the ascii art :)