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# Volumes of Rotation

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1. Prove that the volume of a solid generated by completely rotating the function y= 6/(2x + 1)^1/2 about the x-axis, x=0 and x=4 is 36pi ln3 units cubed

y^2= 36/ (2x+ 1)^1/4

V = pi [18ln(2x+1)^1/4] with 4 at top of bracket and 0 at bottom

just wondering what you do with the power in this case 1/4???

2. Remember that
3. (Original post by Kvothe the Arcane)

Remember that
duh thanks

when i do it properly i then get
[(18ln9} - (18 ln1)]
4. (Original post by Custardcream000)
duh thanks
when i do it properly i then get

[(18ln9} - (18 ln1)]
Remember that
And or more simply that

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Updated: October 9, 2016
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