# Trouble with the unit normal vector for stokes theorem

1. May 9, 2012

### hivesaeed4

We're given x^2+2*y^2=1.
so x^2=1-2y^2

now using distance formula
d^2=x^2+y^2
since x^2=1-2y^2, substituting it in the distance formula we get:
d^2=1-2y^2+y^2=1-y^2;
differentiating and then setting the eq to 0 we get;
0=-4y
or y=0. now x^2=1-2y^2=1
so x=+-1
so point having min distance form origin is (+-1,0)

using the distance formula now
d^2=x^2+y^2
d=sqrt(1+0)=1

2. May 9, 2012

### hivesaeed4

Sorry. Wrong post. I intended to preview it but posted it by mistake.