(adsbygoogle = window.adsbygoogle || []).push({}); 1. Hi, I'm confused on the method of calculating the power of the sawtooth function.

In my textbook the the general formula for claculating the power is

definition 1. http://img210.imageshack.us/img210/5091/75697758.jpg [Broken]

where the limit approaches infinity and the limits are -T/2 to T/2.

For periodic function they say this can be simplfiied to just

definition 2. http://img156.imageshack.us/img156/5962/54601684.jpg [Broken]

so now the T value is actually the period (finite), and the limits are also the finite numbers where the period is from.

For the SAWTOOTH function I know it is periodic so doing with the function equal to f(x) = Ax from for example -1 to 1 (period) and so T = 2

gets the answer that the power is

Px = A^2/3

If i just use the general formula I get infinity!!!

so for periodic functions is it NECESSARY that you HAVE to use definition 2, and you cannot use definition 1?

example when I use defintion 1 for the saw tooth

i get

lim 1/T A^2 [t^3/3)] limits are from T/2 to - T/2

T-> infinity

so you get

lim 1/T A^2 (T^3/4)

T-> infinity

=

lim A^2 (T^2/4)

T-> infinity

= infinity!!

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# Power of a Sawtooth Function

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