Calculate Future Sales of Calculus and You Text

[MathNoob123]

Homework Statement

Sales of the text Calculus and You have been declining continuously at a rate of 4% per year. Assuming that Calculus and You currently sells 4800 copies per year and that sales will continue this pattern of decline, calculate total future sales of the text.

Homework Equations

integral of a to infinity f(x)dx=lm of M>>infinity of integral of a to M f(x)dx

The Attempt at a Solution

I set the problem as integral of 0 to M 4800(0.96)^t dt and computed it, but my answer was incorrect. So then I did the opposite by setting the integral from M to 0, but my answer was still incorrect. Any help would be appreciated. Arigato Gozaimasu!

 

[Dick]

Your formula for 'declining continuously at a rate of 4% per year' is a bit wrong. Don't you want exp(-0.04*t)?