Which integral represents the area of a circle with radius r=3r=3r=3?
∫−3329−x2dx\int_{-3}^3 2\sqrt{9-x^2} dx∫−3329−x2dx
∫03πx2dx\int_0^3 \pi x^2 dx∫03πx2dx
π∫−33(9−x2)dx\pi \int_{-3}^3 (9-x^2) dxπ∫−33(9−x2)dx
∫0329−x2dx\int_0^3 2\sqrt{9-x^2} dx∫0329−x2dx