Find the period of the function

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The function f(x) = e^(3(x - [x])) involves the greatest integer function, which leads to the periodicity of the fractional part of x. The discussion focuses on finding the period T by setting f(x) = f(x + T) and analyzing the equation derived from the properties of the greatest integer function. It is established that the fractional part of x, denoted as {x}, repeats every 1 unit, indicating that the period of the function e^(x - [x]) is also 1. Graphing the function can provide visual confirmation of this periodicity. Ultimately, the period of the function is confirmed to be 1.
utkarshakash
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Homework Statement


f(x)=e3(x-[x])
[] denotes greatest integer function

Homework Equations



The Attempt at a Solution


f(x)=f(x+T)

e3{x}=e{x+T}
Taking ln of both sides
3{x}=3{x+T}
{x}={x+T}

x-[x]=x+T-[x+T]
T=[x+T]-[x]
 
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Now you have to find T which satisfy this equation.
Alternatively, graph x-[x], the period is obvious in the graph.
 
mfb said:
Now you have to find T which satisfy this equation.
Alternatively, graph x-[x], the period is obvious in the graph.

T=[x]+t-[x]
0=0

How to find T?
Also why you are asking me to draw the graph of x-[x] when the question says e raised to x-[x]?
 
utkarshakash said:
Also why you are asking me to draw the graph of x-[x] when the question says e raised to x-[x]?

Give it a try at least. ;)

You see that x-[x] which is equivalent to fractional part of x repeats itself after 1. The period of e^(x-[x]) is obvious.
 
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