How do I tell Wolfram Alpha that I want the fourth derivative of y in a differential equation?

Question

For example, how would I enter y^(IV) - 16y = 0?

typing out fourth derivative, and putting four ' marks does not seem to work.

Answer 1

Input:

y''''[x]

http://www.wolframalpha.com/input/?i=y''''(x)+-+16y(x)+%3D+0.

Answer 2

Typing y'''' - 16y = 0 or (d^4/dx^4 y) - 16y = 0 both seem to work.

Answer 3

The expression

solve y'''' - 16 y = 0 for y

seems to work.

Link to result.