y x 0, y, x y Function x , C 3 Cos 3 x 2 C 2 Sin 3 x 2

DSolve@y'''@xD+y@xD==0,y,xD
Input:
DSolveAy H3L HxL + yHxL 0, y, xE
Exact result:
::y ® FunctionB8x<, ã-x C@1D + ãx2 C@3D CosB
3 x
2
F + ãx2 C@2D SinB
Generated by Wolfram|Alpha (www.wolframalpha.com) on June 15, 2016 from Champaign, IL.
© Wolfram Alpha LLC— A Wolfram Research Company
3 x
2
FF>>
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