The sum of the squares of two positive numbers is 200; their minimum product is
(A) 100
(B)
(C) 28
(D)
(E) none of these
The first-quadrant point on the curve y^2 x = 18 that is closest to the point (2, 0) is
(A) (2,3)
(B)
(C)
(D)
(E) none of these
If h is a small negative number, then the local linear approximation for is
(A)
(B)
(C)
(D)
(E)
If f (x) = xe−x, then at x = 0
(A) f is increasing
(B) f is decreasing
(C) f has a relative maximum
(D) f has a relative minimum
(E) f ′ does not exist
