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Show that the given general solution satisfies the given differential equation, showing all work carefully. Do NOT do this by solving the given differential equation, but rather prove that the whole general solution makes the equation true.

DE= x^2y''- 8xy +8y=16
Gen. Sol y=c1x+c2x^8+2

1 Answer

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Step-by-step explanation:

Differentiating the solution, we have ...

y' = c1 +8c2x^7

y'' = 56c2x^6

Putting this into the DE, we have ...

x^2y'' -8xy' +8y = 16 . . . . . . . different from your problem statement

x^2(56c2x^6) -8x(c1 +8c2x^7) +8(c1x +c2x^8 +2) = 16

56c2x^8 -8c1x -64c2x^8 +8c1x +8c2x^8 +16 = 16

x^8(56c2 -64c2 +8c2) +x(-8c1 +8c1) +16 = 16

0 +16 = 16 . . . . QED

User Peter Birdsall
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