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**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?

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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