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The exact value of the definite integral $\int_{-3}^{3} \sqrt{9-x^2}\,dx$ is $\frac{9\pi}{2}$. This is derived by interpreting the integral as the geometric area of the upper semicircle of a circle with radius 3.

Conditions: Interpret the integral as area under the graph on $[-3,3]$.; Recognize the graph as the upper semicircle of radius 3.; Exact equality for the displayed definite integral.

The exact value of the definite integral $\int_{-3}^{3} \sqrt{9-x^2}\,dx$ is $\frac{9\pi}{2}$. This is derived by interpreting the integral as the geometric area of the upper semicircle of a circle with radius 3.

Conditions: Interpret the integral as area under the graph on $[-3,3]$.; Recognize the graph as the upper semicircle of radius 3.; Exact equality for the displayed definite integral.