Surface area of a solid of revolution: Why does not $ \int_{b}^{a} 2\pi \,f(x) \,dx $ work?
7241
Areas versus volumes of revolution: why does the area require approximation by a cone?
90246
Area of an ellipse. (Calculus)
27910
How to evaluate $\int_0^{2\pi} \frac{d\theta}{A+B\cos\theta}$?
158656
Surface area calculation of sphere segment.
127711
Evaluating $\int_{0}^{1}\int_{0}^{1}\sqrt{x^{2}+y^{2}}dxdy$ using polar coordinates.
138060
Using NSolve in the complex plane
96414
Using residues to evaluate the integral $\int_{-\pi}^{\pi} \frac{\cos(n\theta)}{1-2a\cos(\theta)+a^2}d\theta$, $|a|<1$
145364
units in indefinite integral
67656
Intrinsic vs. extrinsic properties of surfaces
134823
How to find the area of any irregular shape?
49444
Why isn't $e^{2\pi xi}=1$ true for all $x$?
47779
Why does this integral have a complex component?
43319
Surface area inside cylinder
35589
Exact area using limits and Riemann sum
69203
Calculus proof for the area of a circle
31063
Evaluating $\int_0^2(\tan^{-1}(\pi x)-\tan^{-1} x)\,\mathrm{d}x$
96023
Prove: $\int_\gamma \bar z \, dz=2i\operatorname{Area}(G)$