Volumes about the Y-Axis (1 Viewer)

flon

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The curve y=x^3 is rotated about the y-axis from y = 0 to y= 1.

Find the value of the solid formed.

Thanks in advance.
 

GUSSSSSSSSSSSSS

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回覆: Volumes about the Y-Axis

y = x^3 --> x = y^(1/3)
volume = piS[f(y)]^2 . dy OR piS[x^2]dy
therefore

volume = pi.S[y^(2/3)]dy ...........limits: 1 --> 0
=pi[(3/5)y^(5/3)] ...........limits: 1 --> 0
=3pi/5
 
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Fortify

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You guys forgot to x^2.

V = pi [int] x^2 dy ?
 

Fortify

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x^2 = y ^2/3

V = pi [int] y^2/3 dy with limits of 1 and 0
V = pi [3/5 * y ^ 5/3 ] with limits of 1 and 0
V = pi [3/5 - 0]
V = 3pi/5 units^3
 

jet

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LOL. I can't believe i forgot that!
+ 1.
 

flon

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LOL

dw jetblack i made the same mistake as you. thats why i couldnt get it right.
 

jet

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Ironically, I put x2 in the formula.....
 

Gibbatron

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In the time it took me to work out how to use the equation editor, everyone else had already posted the answer lol
 

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