- #1
Lazerlike42
- 20
- 0
First, apologies for the notation.. the computer I am currently using does not support the various buttons to create proper notation.
Given h(x)=|x| over [-1,1], extend the definition such that h(x+2)=h(x). That is, make h(x) be a periodic sawtooth function.
Now let hn(x)=(1/2n)h(2nx).
Then define g(x)=sigma[hn(x)]=sigma[(1/2n)h(2nx)] as n goes from 0 to infinity.
Define the sequence xm=1/2m, where m=0, 1, 2, ...
Prove that [g(xm)-g(0)]/[xm-0]=m+1 and use this to prove that g'(0) does not exist.
I really have no idea. The best I have been able to do is to write the function as:
g(x)=sigma[(1/2n)|2nx|] as n goes from 0 to infinity
and then substitute xm for x to yield:
g(x)=sigma[(1/2n)|2n*(1/2m)|] as n goes from 0 to infinity
and simplify it to:
g(x)=sigma[(1/2)n|2n-m|] as n goes from 0 to infinity. Otherwise, I have no idea.
Homework Statement
Given h(x)=|x| over [-1,1], extend the definition such that h(x+2)=h(x). That is, make h(x) be a periodic sawtooth function.
Now let hn(x)=(1/2n)h(2nx).
Then define g(x)=sigma[hn(x)]=sigma[(1/2n)h(2nx)] as n goes from 0 to infinity.
Define the sequence xm=1/2m, where m=0, 1, 2, ...
Prove that [g(xm)-g(0)]/[xm-0]=m+1 and use this to prove that g'(0) does not exist.
Homework Equations
The Attempt at a Solution
I really have no idea. The best I have been able to do is to write the function as:
g(x)=sigma[(1/2n)|2nx|] as n goes from 0 to infinity
and then substitute xm for x to yield:
g(x)=sigma[(1/2n)|2n*(1/2m)|] as n goes from 0 to infinity
and simplify it to:
g(x)=sigma[(1/2)n|2n-m|] as n goes from 0 to infinity. Otherwise, I have no idea.