Volume of the solid coming in negative
- Thread starter math_N00b
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- Nov 24, 2012
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Hello, and welcome to FMH! 
I would begin by writing:
[MATH]dV=\pi(R^2-r^2)\,dx[/MATH]
where:
[MATH]R=1-x^2[/MATH]
[MATH]r=1-\sqrt{x}[/MATH]
Hence:
[MATH]dV=\pi((1-x^2)^2-(1-\sqrt{x})^2)\,dx=\pi(x^4-2x^2-x+2\sqrt{x})\,dx[/MATH]
Can you proceed?
I would begin by writing:
[MATH]dV=\pi(R^2-r^2)\,dx[/MATH]
where:
[MATH]R=1-x^2[/MATH]
[MATH]r=1-\sqrt{x}[/MATH]
Hence:
[MATH]dV=\pi((1-x^2)^2-(1-\sqrt{x})^2)\,dx=\pi(x^4-2x^2-x+2\sqrt{x})\,dx[/MATH]
Can you proceed?