some help with some math

[shmepti]

is there any way to combine these functions into a single sinusoid:
2sin(1000*pi*t + pi/2) + 5sin(2500*pi*t + pi/6) - 15.9sin(6000*pi*t)

Im drawing a blank. I cant remember many of my trig laws anymore. Anyone have any ideas?

 

[Capn]

No, just looked at a plot of it. It's all crazy looking, no way you could get one sin() function to do that if that's what you're looking for.

 

[shmepti]

i was thinking that. Im not really sure what to do. Its actually a problem for my signal processing class. Just trying to look at all options. Thanks for youre help though

 

[BruinEd03]

<< is there any way to combine these functions into a single sinusoid:
2sin(1000*pi*t + pi/2) + 5sin(2500*pi*t + pi/6) - 15.9sin(6000*pi*t)

Im drawing a blank. I cant remember many of my trig laws anymore. Anyone have any ideas? >>



No you can't because they all have different frequencies: one has 1000, another has 2500, and another 6000.

 

[RossGr]

Here are some paths you might persue:

1. sin(a+b) = sina cosb + sinb cosa

the frist term simplfies to 2cos(1000 PI t)

note that all of the frequencys can be expressed as multibles of 500

1000 PI t = 2 * 500 PI t
2500 PI t = 5 * 500 PI t
6000 PI t = 12 * 500 PI t
Here is a link to more
Trig Identies which might be useful

good luck