Recursive Step: if (n,m,r) ∈ A then (n+1,m+2,m+r+2) ∈ A
Prove, using structural induction, that for every .( n , m , r ) ∈ A , 0 ≤ n < m and n + m ≤ r .
such that when R is revolved about the line y=k, the resulting solid has the same volume as the solid resulting when R is rotated about the x-axis. Write an equation involving integral expressions that can be used to find the value of k, and then solve for k.