let v=volume of solid that results when the region enclosed by y=1/x, y=0, x=2, and x=b (0

Question

let v=volume of solid that results when the region enclosed by y=1/x, y=0, x=2, and x=b (0<b<2) is revolved about the x-axis. FInd the value of b for which V=3.

turingtest · Answer

always always always draw it first....

turingtest · Answer

|dw:1347488810601:dw|now what method do you think is best for revolving this around the x-axis? shell or disk?

anonymous · Answer

yes that what i had too. you would use integration?

turingtest · Answer

yes, I would recommend using the disk method of volumes of revolution
what is your radius of each disk?
what are your bounds of integration?

anonymous · Answer

hmmm.

anonymous · Answer

boundaries = 0-2
 and radius = ?

turingtest · Answer

the lower bound is unknown. at x=0 y is undefined, so you can't integrate that with calc1 techniques

turingtest · Answer

we are told that we are revolving the region bounded by y=0, x=2, and x=b where 0<b<2 (so b is some line we have not determined yet, but we know it is between 0 and 2)

turingtest · Answer

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