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Differential equations help please!!

Find the solution to x^3 dy/dx = 2y^2

y=-4/3 and x=2

I have the answer which is (x^2)/(1-x^2) but i can't get to it.

Please help :frown:
Original post by shle3brown
Find the solution to x^3 dy/dx = 2y^2

y=-4/3 and x=2

I have the answer which is (x^2)/(1-x^2) but i can't get to it.

Please help :frown:


Begin by noticing that this is a separable equation, which can be rewritten as

y2.dy=2x3.dxy^{-2} .dy = 2x^{-3} .dx

Now integrate both sides and go from there. Post your working if you get stuck.
Try integrating it!

READ THIS IF YOU ARE STUCK AND WANT TO CHECK THE SOLUTION AND ANSWER!

Spoiler

(edited 6 years ago)
separate the variables as RDK as shown. if you prefer you could move the 2 to the left; it would appear as 1/2.

once the separation is complete you integrate both sides. you use a single constant of integration; this is usually written on the right hand side.
Original post by YasinZahra
Try integrating it!

x^3 dy/dx = 2y^2

There might be some mistakes though, I apologize for that.

Please amend your post - full solutions [no I didn't check it] are NOT allowed in the Maths forum.
Original post by Muttley79
Please amend your post - full solutions [no I didn't check it] are NOT allowed in the Maths forum.


OMG really? Like is this rule made by the TSR team? Sorry I'm not really aware of the rules and stuff here because I'm new.
Original post by YasinZahra
OMG really? Like is this rule made by the TSR team? Sorry I'm not really aware of the rules and stuff here because I'm new.


Yes, it is a TSR rule. Thanks for amending your post - please just give a hiint and don't even put the solution in a spoiler :smile:

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