Find f(x):
f(x)+f'(x)+f''(x)+f'''(x) = 0
I dont know how to solve, but I know to use Wolfram Alpha XD
f(x) = 0
lol
-_-Actually that is just one solution, but there is infinity solutions. Good job! When I saw problem first thing I found f(x)=sin(x) (same for cos, -sin and -cos) but here is solution
Find f(x):
f(x)+f'(x)+f''(x)+f'''(x) = 0