Problem of the Week

Problem 36 Hint

Following CMS Open Evening on 15th October, this is a hint to the problem and to provide those that attended the open evening a chance and some time to submit solutions before it is released.

Due to this, the solution for both problems will be delayed.

Apologies for the late notice.

We would like to emphasise that partial solutions are acceptable and we cannot wait to see your responses!

a) z^{-1} = \frac{1}{z}. Observe what happens when you square w.

b) Divide by z^2 on both sides, and see what you can do to the left side of the equation by substituting z terms with w terms from a).

c) Consider division of a different power of z on both sides of the equation. Think about what made division by z^2 useful in b).

d**) It may prove useful to write the polynomial as (w-a)(w-b)(w-c)(w-d)=0. Degree 8 means the highest power of z is 8.

e**) The technique you have used in previous parts thought about in a deeper sense. If a value of z was a solution, what happens when you use the value of \frac{1}{z}? If z is between -1 and 1, can \frac{1}{z} be between -1 and 1?

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