The function is proposed as a solution of the differential equation

MATHEMATICS · Single correct · AP · Calculus AB · Differential Equations · Differential Equations

Problem

The function

y=\cosh 3x

is proposed as a solution of the differential equation

y''-ky=0

. What is the value of

k

that makes this true for all real numbers

x

? (a)

k=6

(b)

k=9

(c)

k=3

(d)

k=12