Question

What is the exponential decay formula?

Answer 1

There are different ways of representing the Half-Life (exponential decay):

1) `A=A_0 * 2^(-t/T_(1/2))`

`A`: Final amount
`A_0`: Initial amount
`-t`: time
`T_(1/2)`: the half-life

2) `A=A_0*e^(-kt)`

`A`: Final amount
`A_0`: Initial amount
`-k`: decay constant
`t`: time

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