Define for all real satisfying

MATHEMATICS · Single correct · AP · Calculus AB · Analytical Applications of Differentiation · Analytical Applications of Differentiation

Problem

Define

f_q(x)=\dfrac{1}{x^{2}+q}

for all real

x

satisfying

x^{2}+q\neq 0

. For which values of

q

f_q

concave up for every

x

in its domain? (a)

q<0

(b)

q>0

(c)

q=0

(d)

q\le 0