Rearrange to get:
y' + 3y/x = 6(x^4)*[y^(1/3)]
This is the form of a Bernoulli differential equation
so make u = y^(1-[1/3]) = y^(2/3), y = u^(3/2) = u^1.5
u'= (2/3)*[y^(-1/3)]*(y') (differentiate with respect to x)
y' = (3/2)(y^[1/3]) * (u')
Now substitute everything in.
[ (3/2)([u^1.5]^[1/3]) * (u') ] + 3*[u^1.5]/x = 6(x^4)*([u^1.5]^[1/3])
Looks messy, but [u^1.5]^[1/3] = u^0.5, and divide everything by u^0.5 to get:
(3/2)(u') + 3*u/x = 6(x^4)
u' + 2u/x = 4(x^4)
Integrating factor is x^2
(x^2)u' + 2xu = 4(x^6)
([x^2]*u)' = 4(x^6)
Integrate both sides with respect to x
(x^2)u = (4/7)(x^7) + C
u = (4/7)(x^5) + C/(x^2)
y^(2/3) = (4/7)(x^5) + C/(x^2)
y = [ (4/7)(x^5) + C/(x^2) ]^(3/2) <-------Final Answer
y' + 3y/x = 6(x^4)*[y^(1/3)]
This is the form of a Bernoulli differential equation
so make u = y^(1-[1/3]) = y^(2/3), y = u^(3/2) = u^1.5
u'= (2/3)*[y^(-1/3)]*(y') (differentiate with respect to x)
y' = (3/2)(y^[1/3]) * (u')
Now substitute everything in.
[ (3/2)([u^1.5]^[1/3]) * (u') ] + 3*[u^1.5]/x = 6(x^4)*([u^1.5]^[1/3])
Looks messy, but [u^1.5]^[1/3] = u^0.5, and divide everything by u^0.5 to get:
(3/2)(u') + 3*u/x = 6(x^4)
u' + 2u/x = 4(x^4)
Integrating factor is x^2
(x^2)u' + 2xu = 4(x^6)
([x^2]*u)' = 4(x^6)
Integrate both sides with respect to x
(x^2)u = (4/7)(x^7) + C
u = (4/7)(x^5) + C/(x^2)
y^(2/3) = (4/7)(x^5) + C/(x^2)
y = [ (4/7)(x^5) + C/(x^2) ]^(3/2) <-------Final Answer
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All you have to do is reduce the expression 6 x^4 y^1/3 by removing a factor of 3 from the numerator and the denominator leaving you with: 2x^4y - 3y/x