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Re: How would you find the parabolas determined by points {1,2}, {1,1}, {2,1}?
Posted:
Jan 6, 2014 7:58 PM


On Sunday, January 5, 2014 7:21:37 PM UTC8, Hetware wrote: > Given the three points (1,2), (1,1), and (2,1). (a) Find a parabola > > passing through the given points having its axis parallel to the xaxis. > > (b) Find a parabola passing through the given points having its axis > > parallel to the yaxis. > > > > I set up the equation > > > > (yk)^2=4p(xh) > > > > and substituted the given ordered pairs and crunched the numbers. It > > became (rather) messy, but I arrived at the given solution. I'm > > wondering if there is a more efficient approach to the problem. > > > > Answers: > > > > 7(y^2)3y+6x16=0 > > 7(x^2)9x6y4=0
Why not use the Lagrange interpolation formula? See http://en.wikipedia.org/wiki/Lagrange_polynomial .



