# Formulating a NLP

• April 28th 2010, 01:55 AM
lpd
Formulating a NLP
Hi I'm a bit stuck in this question.

Consider the problem of finding the point on the curve y = x^3/2 that is closest to the point (1, 0).

Model this problem as a non-linear program (NLP) with a single equality constraint.

min (x-1)^2 + y^2
subject to y = x^(3/2)

or would I need... a squareroot on my objective function?
• April 28th 2010, 02:24 AM
HallsofIvy
You do NOT need a square root. The derivative of $u^2$ is 2uu' which is 0 only if u= 0 (which cannot happen here, the curve does not go through the point) or if u'= 0 which is what you want.