- #1

- 169

- 0

Can someone give me an example to which this applies? Can you use any function in place of "u"?

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter lLovePhysics
- Start date

- #1

- 169

- 0

Can someone give me an example to which this applies? Can you use any function in place of "u"?

- #2

rock.freak667

Homework Helper

- 6,223

- 31

and for u>0 ,|u|=u

and for u<0,|u|=-u

for example take |x|

[tex]\frac{d}{dx}(|x|)=\frac{x}{|x|}[/tex]

for x>0 ,|x|=x

and so [itex]\frac{d}{dx}(x)=\frac{x}{x}=1[/itex] which is true. Take x<0 and it'll also hold true.

- #3

HallsofIvy

Science Advisor

Homework Helper

- 41,847

- 967

Do what you always do with an absolute value: consider cases u(x)>0 and u(x)< 0 separately.

Share: