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 Three Intercepts (Posted on 2006-06-19)
Given the information that the graph of a function has a y-intercept at (0,1) and exactly two x-intercepts at (2,0) and (4,0), how many different functions can you find that pass through these three points?

Note: there are infinite families of functions such as high degree polynomials which pass through them, so a single example would suffice for them. Also disallowed would be piecewise function and functions with artificially restricted domains.

 No Solution Yet Submitted by Jer Rating: 2.0000 (2 votes)

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 The Old Kitchen Sink | Comment 2 of 7 |
For any nonzero integer k,

y=sinc(k*pi*x/2)

=(sin(k*pi*x/2))/(k*pi*x/2) for nonzero x,

=1 for x=0

is 1 at x=0 and is zero at when x is any nonzero multiple of 2/k (including 2 and 4). Also, any of these can be multiplied by any  function of the real variable x which equals 1 at x=0, for example by exp(a*x).

See MathWorld or Wikipedia entries for Sinc Function.

Edited on June 19, 2006, 10:58 pm
 Posted by Richard on 2006-06-19 22:35:30

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