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Lukybear

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y=2/(2x-6)

Find the volume of the solid of revolution by rotating the curves around the x axis, x=5, x=6.

Do not get the method of this question. Please help!
 

addikaye03

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y=2/(2x-6)

Find the volume of the solid of revolution by rotating the curves around the x axis, x=5, x=6.

Do not get the method of this question. Please help!
V=pi int. (y^2) dx where y= 2/2x-6 which =1/(x-3). Therefore y^2=1/(x-3)^2

V=|-pi1/[x-3]|from 5 to 6

pi(1/2-1/3)=pi/6 unit sq
 

Lukybear

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O darn. Didnt know recognise the ability to simplify. How stupid.

But what if it was give 5/(2x-6)??
 

annabackwards

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O darn. Didnt know recognise the ability to simplify. How stupid.

But what if it was give 5/(2x-6)??
The only thing would be the simplification.
You'd integrate ^2 = 25/4(x-3)^2
Which would equal 25pi/4x6 = 25pi/24
 

Lukybear

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O thx so mcuh. Forgot about that identy. O man, im screwed for my tests upcoming.
 

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