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Find the volume V of the solid obtained by rotating the region bounded by the curves y = 5 sin(x) and y = 5 cos(x) about the line y = -1. The value of x ranges from 0 to 4.

User Psykeron
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1 Answer

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Final answer:

The volume of the solid obtained by rotating the region between y = 5 sin(x) and y = 5 cos(x) around the line y = -1 can be calculated using integral calculus, taking into account the symmetry of sin² and cos² over a complete cycle.

Step-by-step explanation:

The volume V of a solid created by rotating a region around a line can be found using the disk or washer method from calculus. In this case, we are rotating the region bounded by y = 5 sin(x) and y = 5 cos(x) around the line y = -1.

The region is rotated about this line from x = 0 to x = π/2, where both functions complete a quarter cycle and intersect. From the formula:

V = π ∫ (R² - r²) dx

where

R and r are the outer and inner radii from the line of revolution to the curves

the volume can be calculated.

However, since the sine and cosine functions are merely phase-shifted versions of each other, their squares will result in the same average value over a complete cycle.

Therefore, the integral will involve cos²(x) or sin²(x) and their average value over the interval, which will simplify the calculation of the volume.

User Seethrough
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