Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
Let and be the roots of . Answer without finding the roots themselves.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Start. and .
(a) .
A rule for the powers. Each root satisfies , so . Adding for and : , with and .
(b) and (c) , , , and .
(d) , so .
(e) Sum: . Product: . So and .
Check. The roots are ; raising them to the powers directly gives the same values of .
Watch out. is not : it is , which the rule above gives too.
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