implemantation of an equation.

[bevag]

Hi,
I am a new user and I need help.
My problem is that have some data(x,y) and I done a chart for them
However, I need to draw a curve which has this type: y=ax/(1+ax) an
then I draw the erros. I don't know how I can implement this equation
Could someone help me? It is urgent for me.
In the attachment image you can see what I want exactly.
Thanks

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[cartera]

use the trendline with your chart

 

[bevag]

The trendline is defined by excel (linear, exponential, power etc.).
don't want to add one fo these trendlines. I want to use as trendlin
this equation y=ax/(1+ax

 

[Tushar Mehta]

Ummm...you can rewrite the equation y=ax/(1+ax) as
1/y = 1/(ax)+1 as long as you have no y=0 or x=0 points.

Substitute y'=1/y, x'=1/x and you get y'=a'x'+1, with a'=1/a.

Solve the linear equation with LINEST or a chart trendline.

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Regards,

Tushar Mehta
www.tushar-mehta.com
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