\ \
The principal amount .
Amount after is
.
Formula for continuous compounding: .
Substitute ,
and
.
Apply ln on each side.
\Substitute the value of .
.
The rate of interest .
The amount is doubled in years.
The amount .
Compounded continuously.
\Formula for continuous compounding: .
Apply ln on each side.
\Apply power rule of logarithms: .
Substitute the value of .
\ \
Substitute .
.
Initial investment | \Annual rate | \Time to double | \Amount after ![]() | \
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