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Trey

Guest

Deter. Definite Integral

I had a question on a w/s the other day in class and was looking at it.
Deter. the definite integral of the grap when y=x^3, y=1, x=0. (graph that) then there were 3 questions.

1) as it revolves around x-axis deter the definite integral
2) as is revolves around y-axis " "
3) as is revolves around x=2 " "

I think that is how the question went. If anything sounds confusing please let me know and I can maybe explain it better.

JaneFairfax

Member

Registered: 2007-02-23

Posts: 6,868

Re: Deter. Definite Integral

1)

2)

3) Er, do you mean the area between the curve, the x-axis and the line x=2? Find the volume of the solid of revolution when this area is spun round x=2?

Well, if you shift the curve to the left by 2, you get y = (x+2)[sup]3[/sup], which cuts the the y-axis at (0,8). Now rotate the area about the y-axis.

trey

Guest

Re: Deter. Definite Integral

yea...as it revolves around x=2 which is the dotted line when you draw it on the graph