Calculus: Solve the following differential equation

AI Thread Summary
The differential equation 8y'' - 4x = 0 was solved, yielding the function y = (x^3)/12 - 3x + 2. Initial conditions were provided as y=2 and y'=-3 at x=0, which clarified the context of the problem. There was some confusion regarding whether the solution sought was the function or the specific value at x=0. Ultimately, the consensus is that the function y = (x^3)/12 - 3x + 2 is correct. The discussion emphasizes the importance of accurately interpreting initial conditions in differential equations.
laker_gurl3
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Solve the following differential equation:

8y'' - 4x = 0 Where y= 2 and y'=-3 and x= 0

first i did this:

y' = (1/4)x^2

y' = (1/4)x^2 - 3

then antideriv again to get the final answer:

y = (x^3)/12 - 3x + 2

is the final answer 2 or this one :y = (x^3)/12 - 3x + 2

THANK YOU!
 
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laker_gurl3 said:
Solve the following differential equation:

8y'' - 4x = 0 Where y= 2 and y'=-3 and x= 0

first i did this:

y' = (1/4)x^2

y' = (1/4)x^2 - 3

then antideriv again to get the final answer:

y = (x^3)/12 - 3x + 2

is the final answer 2 or this one :y = (x^3)/12 - 3x + 2

THANK YOU!

I think they are looking for the function y = f(x) rather than the specific value y = f(0). You would not need to solve the equation to find the latter, because it is given. The wording of the intitial conditions would be better stated as

Where y= 2 and y'=-3 at (or when) x= 0
 
so did i get it wrong this is all it said for the question:

Solve the following differential equation:

8y'' - 4x = 0 Where y= 2 and y'=-3 at x= 0
 
laker_gurl3 said:
so did i get it wrong this is all it said for the question:

Solve the following differential equation:

8y'' - 4x = 0 Where y= 2 and y'=-3 at x= 0

You did it correctly. I thought you were just trying to decide between the function you found and the specific value y = 2.

y = (x^3)/12 - 3x + 2 looks good to me.
 
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