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asdf1
Aug27-05, 09:27 AM
In the problem, y`= 1+0.01y^2
the first i took was
dy/(1+0.01y^2)=dx
however, i'm stuck on the integration step...
can someone help?

TD
Aug27-05, 09:30 AM
\int {\frac{{dy}}{{1 + 0.01y^2 }}} = \int {\frac{{dy}}{{1 + \left( {\frac{y}{{10}}} \right)^2 }}} = 10\int {\frac{{d\left( {\frac{y}{{10}}} \right)}}{{1 + \left( {\frac{y}{{10}}} \right)^2 }}}

The last one smells arctan-ish :smile:

asdf1
Aug27-05, 09:43 AM
jeepers! thanks for reminding me about the arctan-ish thingy...
crud, totally forgot about that one~
:)

TD
Aug27-05, 09:49 AM
No problem; but never forget the arctan hehe :biggrin: