Problem #15: Consider the following function.
f(x) = \frac{1}{\sqrt{4\pi}}e^{-x^2/2}
(note that 4\pi is under the square root in the denominator)
Find the largest interval(s) on which \(f\) is concave up.
(A) (-?, e) (B) (-?, 0) (C) (0, ?) (D) (-?, -1), (0, 1) (E) (-1, 0), (1, ?) (F) (-?, -1), (1, ?) (G) (e, ?)
(H) (-1, 1)