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1. The diagram shows the region R which lies between the line y=x and the curve y=x^3 for x>0.
Find the volume of the solid formed when the Region R is rotated about the x-axis?
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2. (Original post by calster102)
The diagram shows the region R which lies between the line y=x and the curve y=x^3 for x>0.
Find the volume of the solid formed when the Region R is rotated about the x-axis?
Have you studied Solids of Revolution yet?
3. (Original post by nebelbon)
Have you studied Solids of Revolution yet?
Yes I don;t know how to find the other value of x to work it out tho i;ve posted a picture above btw
4. (Original post by calster102)
Yes I don;t know how to find the other value of x to work it out tho i;ve posted a picture above btw
The graphs meet when x^3 = x
5. (Original post by TenOfThem)
The graphs meet when x^3 = x
Using that what am i supposed to find because all we have is x on both sides nothing else...
6. (Original post by calster102)
Using that what am i supposed to find because all we have is x on both sides nothing else...
Solving that equation will tell you the x-coordinates of the points where the curve and the line intersect. You will need these for your limits of integration.
7. (Original post by davros)
Solving that equation will tell you the x-coordinates of the points where the curve and the line intersect. You will need these for your limits of integration.
Okay so x^3=x
when solved gives what?? route cubed x?????
or do you factorise x^3-x=0???
8. how exactly do you find the volume of revolution when there is 2 equations?????????????????
9. (Original post by calster102)
Okay so x^3=x
when solved gives what?? route cubed x?????
or do you factorise x^3-x=0???
You can almost see what the solutions are going to be without working anything out

But if you're struggling, then treat it as a 'proper' equation and factorize it.
10. (Original post by calster102)
Okay so x^3=x
when solved gives what?? route cubed x?????
or do you factorise x^3-x=0???
yes

x(x^2-1) = 0

Will factorise further - I assume that you had the x=0

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Updated: December 1, 2014
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