Solved

if y'=(1/x') therefore x'=(1/y')   so d(5)y/dx(5) =y''''' and x'''''=1/[d(5)y/dx(5)]=dx(5)/d(5)y

Posted on 2016-09-06
9
41 Views
Last Modified: 2016-10-10
I had this question after viewing Is (dx²)/(d²y) is acceptable as second derivative?.
0
Comment
Question by:John Sebastian
  • 5
  • 3
9 Comments
 
LVL 27

Expert Comment

by:aburr
ID: 41786375
Your equation has difficulties with the meaning that you attach to it. Consider your premise

if y'=(1/x')

It is wrong. Try it on a simple function like y = x^3. It will not work.     (If you have trouble, ask)
0
 

Author Comment

by:John Sebastian
ID: 41789244
y=x^3

y'=3x²

1=3x²x'   →x'=1/3x²

y'=1/x' is correct
0
 
LVL 27

Expert Comment

by:aburr
ID: 41789959
1=3x²x'  
I have a hard time figuring out how you got this relationship.
0
 

Author Comment

by:John Sebastian
ID: 41790326
Dx/dy
0
Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

 
LVL 27

Expert Comment

by:aburr
ID: 41790525
but if y = x^3      x = y^(1/3)
dx/dy is then =
                                (1/3)y^(-2/3)      not 3x²x'
0
 

Author Comment

by:John Sebastian
ID: 41790782
1=3x²x'→x'=1/3x²→x'=1/3(y⅓
→x'=1/3(y⅔)
Note that x=y^(1/3)
Therefore they have the same answer... Am i wrong?
0
 
LVL 27

Expert Comment

by:aburr
ID: 41791935
"Am i wrong?"   no    I am
I put one too many inverses in my calculations
0
 
LVL 27

Accepted Solution

by:
BigRat earned 500 total points (awarded by participants)
ID: 41808671
>>y'=1/x' is correct

That is ALWAYS correct simply from the definition of y' (as you have it) since y' = dy/dx and x'=dx/dy and dx/dy*dy/dx=1.

Similarly if you want to write y'' for d²y/dx² then x'' would be d²x/dy² and so y''=x''. And so on and so forth PROVIDED that such differentials exist!
0
 
LVL 27

Expert Comment

by:aburr
ID: 41836561
The only correct answer, (and a good one)
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Any Game advice for ellipses drawing a solar system? 1 66
Probability 2 52
x2 – x2 = x2 – x2 conundrum 12 66
How to install SVN Command Line Client? 5 39
Have you ever thought of installing a power system that generates solar electricity to power your house? Some may say yes, while others may tell me no. But have you noticed that people around you are now considering installing such systems in their …
This article provides a brief introduction to tissue engineering, the process by which organs can be grown artificially. It covers the problems with organ transplants, the tissue engineering process, and the current successes and problems of the tec…
This is a video describing the growing solar energy use in Utah. This is a topic that greatly interests me and so I decided to produce a video about it.
Concerto provides fully managed cloud services and the expertise to provide an easy and reliable route to the cloud. Our best-in-class solutions help you address the toughest IT challenges, find new efficiencies and deliver the best application expe…

932 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

12 Experts available now in Live!

Get 1:1 Help Now