Alternative to remember area and circumference of a circle
Many people can actually remember either:
`pir^2` or `2pir`
But need a nudge to remind them which is area and which is circumference.
To remember which is which:
Just remember `r^2` must be an area
And a single `r` must be a line
So
`\pir^2` = Area
`2\pir` = The line of the circumference
![](/images/user/base/Maths/Logarithms/Reference%20Tables/reference-log-table-1.4df6ee6.jpg)
![](/images/user/base/Maths/Logarithms/Reference%20Tables/reference-log-table-2.d516bb3.jpg)
![](/images/user/base/Maths/Logarithms/Reference%20Tables/reference-anti-log-table-1.b0b0513.jpg)
![](/images/user/base/Maths/Logarithms/Reference%20Tables/reference-anti-log-table-2.f89189d.jpg)