The Lagrange    remainder   R,  after   n   terms,  for some    c   in  the interval    |x| 
2,  is
Since   R   is  greatest    when    c   =   2,  n   needs   to  satisfy the inequality
Using   a   calculator  to  evaluate        successively    at  various integral
values  of  x   gives   y(8)    >   0.01,   y(9)    >   0.002,  y(10)   <   3.8 ×   10 −4   <   0.0004.
Thus    we  achieve the desired accuracy    with    a   Taylor  polynomial  at  0   of
degree  at  least   10.
(D) On  your    calculator, graph   one arch    of  the cycloid for t   in  [0,2π]  and
(x,y)   in  [0,7]   ×   [−1,3]. Use disks;  then    the desired volume  is
(C)  In  the     first   quadrant,   both   x    and    y    must    be  positive;  x(t)     =  et   is
positive    for all t,  but y(t)    =   1   −   t   2   is  positive    only    for −1  <   t   <   1.  The arc