How to limit input?

[pinto]

Hi!

Say A1 is an input cell and B1 is an output cell, say 100 + A1 -A1^2.

Now, how would I limit this input cell so that I can only enter values for which B1>=0? Is this possible?

Thanks for help!

 

[gsbelbin]

Try selecting A1 and click Data, Validation. Then on the Settings tab select custom from the drop down and enter the following in the Formula box

= 100 + A1 -A1^2>=0

Click OK and that should do it.

Cheers

Gordon