# Thread: convert function simpler terms for which we know the Laplace transforms of each term

1. ## convert function simpler terms for which we know the Laplace transforms of each term

"To find the inverse Laplace transform of a complicated function, we can convert the function to a sum of simpler terms for which we know the Laplace transform of each term."

The sentence is confusing. I cannot understand the part "for which". What for which modifies? Why should we use it as it to be instead of simply using "which" ? What is the role of "for" here?

Source: Control Systems Engineering by Norman S. Nise.

Thank you.

2. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

For which refers to "simpler terms". The author could have written "we can convert the function to a sum of simpler terms whose Laplace transforms we know."

3. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

Originally Posted by GoesStation
For which refers to "simpler terms". The author could have written "we can convert the function to a sum of simpler terms whose Laplace transforms we know."
What if we omit "for" in the original as "To find the inverse Laplace transform of a complicated function, we can convert the function to a sum of simpler terms which we know the Laplace transform of each term?

Thank you.

4. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

No, you can't omit "for."

5. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

What about because instead of for which: "To find the inverse Laplace transform of a complicated function, we can convert the function to a sum of simpler terms because we know the Laplace transform of each term?

Thank you.

6. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

That's grammatically correct but it changes the meaning. Here's what the original sentence means in outline form.

To find the inverse Laplace transform of a complicated function:
1) Find a set of simpler terms. We have to know the Laplace transform of each term.
2) Convert the function to a sum of these simpler terms.

7. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

Originally Posted by GoesStation
That's grammatically correct but it changes the meaning. Here's what the original sentence means in outline form.
To find the inverse Laplace transform of a complicated function:
1) Find a set of simpler terms. We have to know the Laplace transform of each term.
2) Convert the function to a sum of these simpler terms.

I can get the meaning but the function of "for" here is still a secret for me

Thank you.

8. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

Do you understand "for which" in the following?

A: I have seen two plants I like. There are two different names for one of them. Which plant should I buy?
B: Buy the one for which there are two names. It sounds more interesting!

A: There are three combination-locked boxes in that room. I want to open all of them.
B: What's the problem? Open them!
A: I can't. I only have the combination for two of them.
B: Then open the two boxes for which you know the combination.

9. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

Originally Posted by emsr2d2
Do you understand "for which" in the following?

A: I have seen two plants I like. There are two different names for one of them. Which plant should I buy?
B: Buy the one for which there are two names. It sounds more interesting!

A: There are three combination-locked boxes in that room. I want to open all of them.
B: What's the problem? Open them!
A: I can't. I only have the combination for two of them.
B: Then open the two boxes for which you know the combination.
Yes, I understand them but can we change, for example, last one as "Then open the two boxes which you know the combination for" ?

Thank you.

10. ## Re: convert function simpler terms for which we know the Laplace transforms of each t

Yes, you can.

Page 1 of 2 1 2

#### Posting Permissions

• You may not post new threads
• You may not post replies
• You may not post attachments
• You may not edit your posts
•