Example: Compute p by sampling uniformly in the square U with sides of length 2. Then we get as follows… and this is a FPRAS. However if we want to compute the volume of an n dimensional sphere we get troubles: to evaluate p we may consider the hypercube inscribed in the sphere, its sides having length 2 Ön-1 ,so the hypercube volume is 2n n-n/2 . Then we get as follows and…

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