Solving differential equations

wezzo62
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Find the general solution to: dy/dx = 3x2y

I tried saying u = 3x2 and v = y
then du/dv = 6x and dv/dy = 1

and get 3x2 + 6xy but now i think iv gone completely the wrong way around this . . . .
 
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Try using separation of the variables.
 
wezzo62 said:
Find the general solution to: dy/dx = 3x2y

I tried saying u = 3x2 and v = y
then du/dv = 6x and dv/dy = 1

and get 3x2 + 6xy but now i think iv gone completely the wrong way around this . . . .

You can swing the y over to the left hand side (LHS) of the equation, and the dx to the RHS.
This gives you two integrals. Do them, and see what happens.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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