$\"\"$

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Continuous income flow $\"\"$ .

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Annual interest rate is $\"\"$ and time $\"\"$ years.

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Find the present value of the amount.

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Present value $\"\"$ .

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Substitute corresponding values in the formula.

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$\"\"$

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$\"\"$ $\"\"$

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Consider $\"\"$ .

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Find the integral using integration by parts.

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Formula for integration by parts: $\"\"$ .

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Here $\"\"$ and $\"\"$ .

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Consider $\"\"$ .

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Apply derivative on each side with respect to $\"\"$ .

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$\"\"$ .

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Consider $\"\"$ .

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Apply integral on each side.

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$\"\"$

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Substitute corresponding values in integration by parts formula.

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$\"\"$

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$\"\"$

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$\"\"$

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Substitute above result in (1).

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$\"\"$

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Present value is $\"\"$ .

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$\"\"$

\

Present value is $\"\"$ .