Diff equation last step of the solution

  • Thread starter Thread starter electron2
  • Start date Start date
Click For Summary

Homework Help Overview

The discussion revolves around a differential equation where the original poster presents an expression involving the step function, u(t), and seeks guidance on further development of this expression. The context involves understanding the representation of the solution in terms of rectangular functions.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants discuss the nature of the expression presented, questioning whether it constitutes a complete solution or if further development is necessary. There are inquiries about the left-hand side of the equation and how to express the solution in terms of rectangular functions.

Discussion Status

The discussion is ongoing, with participants providing hints and references to external resources. Some express frustration over the perceived lack of assistance, while others attempt to guide the original poster towards a clearer understanding of how to manipulate the expression.

Contextual Notes

There are indications of missing information regarding the left side of the equation, which is described as an integral. The original poster's expression is also noted to be a linear combination of step functions, which may require further transformation to fit the desired form.

electron2
Messages
46
Reaction score
0
after solving a long diff question i got

0.5*u(t+1)-0.5*u(t-1)

where u(t) is a step function for t>=0 its 1
and t<0 its 0

my expression looks pretty finite to me

how to continue??
 
Physics news on Phys.org
electron2 said:
after solving a long diff question i got

0.5*u(t+1)-0.5*u(t-1)

where u(t) is a step function for t>=0 its 1
and t<0 its 0

my expression looks pretty finite to me

how to continue??
I don't understand the question. Does your expression form part of an equation? What is the end goal?
 
my expression is the final solution
but i was told that it cam be developed further more

how??
 
electron2 said:
my expression is the final solution
but i was told that it cam be developed further more

how??
You're expression cannot be the final solution since it is not an equation! What is on the left hand side of the equality sign?

However, linear combinations of heaviside (step) functions can often be written in terms of the rectangular function.
 
believe me there is a left side
its some intergral
and its not important

how to write it in terms of the rectangular function?
 
electron2 said:
believe me there is a left side
its some intergral
and its not important
Okay, if you say so.
electron2 said:
how to write it in terms of the rectangular function?
Try googling rectangle function.
 
electron2 said:
i looked it in google
http://en.wikipedia.org/wiki/Rectangular_function
its not helping at all
Well you obviously didn't look hard enough since the answer is virtually given in the second equation!
electron2 said:
how to write it using rectangular functions
I'm here to help you with your work, but I'm not simply going to give you the answer.
 
ok so look at it as if
i asked to solve the whole question
and i showed the solution till some point
and i need to finish it

by saying
"I'm here to help you with your work, but I'm not simply going to give you the answer."

you are not helping at all
you could give a hint
or a article

but you didnt
 
  • #10
electron2 said:
by saying
"I'm here to help you with your work, but I'm not simply going to give you the answer."

you are not helping at all
you could give a hint
or a article

but you didnt
I did give you a hint in post #6, which lead you to an article. I then gave you another hint in post #8, the answer is given there in the second formula on the wiki page!
 
  • #11
the formula is with (t-0.5)

and i have t-1

how to suit it with my expression
 
  • #12
electron2 said:
the formula is with (t-0.5)

and i have t-1

how to suit it with my expression
Let's have a look at the expression,

12bbbf9bd48745e67223553a4c97510d.png


And compare with your expression,

[tex]f\left(t\right) = \frac{1}{2}\left[u\left(t+1\right)-u\left(t-1\right)\right][/tex]

So, what do you have to set tau to, in order to make wiki's expression the same as yours?
 
Last edited:
  • #13
so tao=2

so its f(t)= [rect(t/2)]/2

correct?
 
  • #14
electron2 said:
so tao=2

so its f(t)= [rect(t/2)]/2

correct?
Indeed it is :approve:
 
  • #15
thanks
 

Similar threads

Replies
8
Views
1K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 11 ·
Replies
11
Views
3K
Replies
6
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 105 ·
4
Replies
105
Views
11K
  • · Replies 6 ·
Replies
6
Views
2K
Replies
3
Views
2K
  • · Replies 11 ·
Replies
11
Views
2K