Skip to Content

Surface Area Above a Rectangle for a Function in 3D

Home | Calculus 3 | Surface area | Surface Area Above a Rectangle for a Function in 3D

Find the surface area of Z=4x2Z = \sqrt{4 - x^2} which is above the region RR, a rectangle defined by x[0,1]x \in [0, 1] and y[0,4]y \in [0, 4].

This problem requires finding the surface area of a three-dimensional object defined by a function z=f(x,y)z = f(x, y). Specifically, we are interested in the surface area of the portion of z=4x2z = \sqrt{4 - x^2} that lies above a specific rectangle in the xy-plane. The rectangle is defined by xx values ranging from 0 to 1 and yy values from 0 to 4.

To approach this problem, one would typically make use of concepts from surface area calculations in multivariable calculus. This involves setting up a double integral over the given region RR. The integrand in this situation is derived from the formula for surface area in terms of partial derivatives. Specifically, you would need the square root of 1 plus the squares of the partial derivative with respect to xx and the partial derivative with respect to yy.

Additionally, while working through this type of problem, understanding the geometry and shape of the surface is key. It helps to visualize or sketch the function z=4x2z = \sqrt{4 - x^2} in the context of its intersection with the yzyz-plane to recognize that it forms a segment of a cylinder with its axis along the yy-direction. Recognizing this underlying geometric shape can simplify the task of setting up and evaluating the necessary integrals to find the solution.

Posted by Gregory 2 hours ago

Related Problems

Find the surface area of the portion z=x2+y2z = x^2 + y^2 below the plane z=9z = 9.

Find the surface area of the curve z=4x2z = \sqrt{4 - x^2} above RR which is the rectangle where xx is between 00 and 11 and yy is between 00 and 44.

Find the surface area of the part of the surface Z=x2+2yZ = x^2 + 2y that lies above the triangular region with vertices (0,0)(0, 0), (1,0)(1, 0), and (1,1)(1, 1).

Compute the surface area of a surface given its parametric description. Use the formula:  iintRegionru×rvdudv\ iint_{\text{Region}} \| \mathbf{r}_u \times \mathbf{r}_v \| \, du \, dv where ru\mathbf{r}_u and rv\mathbf{r}_v are the partial derivatives of the position vector with respect to the parameters uu and vv.