so the equation for this would be 1.05\^t \* 1000 = 1000000.

If we divide both sides by 1000 it simplifies to 1.05\^t = 1000

Now take the log of both sides and we can further simplify to t \* log(1.05) = log(1000)

From there it's easy to solve with a calculator.

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P.S. wolfram alpha is a very good online calculator, you can just plug in whole equations and it'll give you a solution.