Graphing and Integration Help (1 Viewer)

[ShawnG]

Hi, I never really ask for help on this forum but I'm in dire need of assistance tonight.
I need to find the stationary and turning points of the curve
y = ln x/x and the x and y intercepts of the same curve. Any help would be greatly appreciated.

Thanks

 

[Timothy.Siu]

u differentiate it and if i did it correctly

i got

y'=(ln x -1)/x^2

which tells us a stat. pt. is at x=e y=1/e
then u can test that to see if its a turning

also for x,y, intercepts x=/= 0 so theres no y intercepts
and ln x=0 when x=1 so thats the x-intercept

i didn't really explain it but to find intercepts, u let x or y =0

 

[tacogym27101990]

i didn't really explain it but to find intercepts, u let x or y =0

you'd hope he already knows this, =]

and also, where is the integration help?

 

[Timothy.Siu]

you'd hope he already knows this, =]

and also, where is the integration help?

what integration?

 

[tacogym27101990]

what integration?

from the heading?

 

[Timothy.Siu]

from the heading?

think he meant differentiation

so i forgot to help...

d/dx (lnx)=1/x
d/dx (x)=1

to differentiate u use quotient rule
d/dx=uv'+vu'

in this case u=lnx and v=x

 

[tacogym27101990]

think he meant differentiation

so i forgot to help...

d/dx (lnx)=1/x
d/dx (x)=1

to differentiate u use quotient rule
[bold]d/dx=(vu'+uv')/v²[/bold]

in this case u=lnx and v=x

fixed

 

[Timothy.Siu]

oopsies