Question 267720
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The area of a circle, given the measure of the radius, is calculated by:



*[tex \LARGE \ \ \ \ \ \ \ \ \ \ A\ =\ \pi{r^2}]


But you have the diameter.  The diameter is two times the radius, so the radius must be 3.  Hence:



*[tex \LARGE \ \ \ \ \ \ \ \ \ \ A\ =\ \pi{3^2}\ =\ 9\pi]


Which is the exact answer.  If you want a numerical approximation, pick a value for *[tex \Large \pi] of sufficient precision to suit you, substitute, and then do the arithmetic.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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