excel function to give the area of a circle?

[bhoward425]

I'm working my way through learning to build spreadsheets. How would I create
the function to give the area of a circle. I know the formula A=PI*r(squared)
but don' know the excel functions. I tried "=(PI)*(Power('diameter
cell'/2),2)" but that wouldn't work.

 

[Niek Otten]

With the radius in A1:

=PI()*A1^2

Or, with the diameter in A1:

=PI()*(A1/2)^2

 

[Bill Sharpe]

I'm working my way through learning to build spreadsheets. How would I create
the function to give the area of a circle. I know the formula A=PI*r(squared)
but don' know the excel functions. I tried "=(PI)*(Power('diameter
cell'/2),2)" but that wouldn't work.

see Excel help for PI.
If radius is in cell A1, either of these formulas should work:
=PI()*A1^2
=PI()*A1*A1

Bill