Originally Posted by

**dankelly07** I have another problem with separable equations, can anyone help?

I need to know how I end up with PI and tan in the answers to these differential equations, its just not making much sense to me at the minute!

so I start with equation

dy/dx = 1+y^2/2+4x

which satisfies y(1) = 1

so this becomes

1/1+y^2 dy = 1/2+4x dx

??

Am I right so far?

then does the LHS

become

tan-1 and do you take the log of the RHS?

can anyone help me through the stages??

I have the solution

i just need to see how this works! especially with PI coming into it, how??

tan(PI/4+1/4ln(|2+4x/6|)).....

Any help would be gr8!