Cosine and Something Else
Geometry
Level
5
Let \(n\) be a positive nonzero integer and
\(k=4n,\)
\(a=x+\sqrt { { x }^{ 2 }-{ k }^{ 2 } }, \)
\(b=x-\sqrt { { x }^{ 2 }-{ k }^{ 2 } }, \)
\(f\left( x \right) =\dfrac { 1 }{ 2 } \dfrac { 1 }{ { k }^{\displaystyle k } } \left( { a }^{ \displaystyle k }+{ b }^{\displaystyle k } \right).\)
For what integer \(n<1000\) does \(f\left( x \right) \) intersect \(\cos\left( x \right) \) the most times between \(-4\pi <x<4\pi \)?
You may want to use a graphing calculator.
by
Michael Mendrin