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I can't figure out this problem...any help would be great. :)

(dy/dx) = (x+1)/(y-1) where y>1

I understand that you separate the x and y and integrate both sides...but I end up with this after integrating:

(1/2)y^2 - y = (1/2)x^2 + x

The answer is supposed to be:

y = 1 + ((x+1)2 + c)^(1/2)

I just can't figure out how to simplify it to that point.......
 
When you do a general integral, you're supposed to include a constant of integration. That's where the "C" came from.

For the rest, multiply through by "2", move everything over onto the left-hand side, and then note that you have a quadratic in "y". Apply the Quadratic Formula to solve for y in terms of x (and C). Get rid of the "±" by noting that y is supposed to be greater than 1.

Eliz.
 
??

I don't understand...if you moved everything over to one side, you would still have two variables on one side...? By quadratic formula do you mean:

(-b + or - (b^2 - 4ac))/2a
 
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