Re: constructible number


Tim.K.K wrote:
a is a constructible positive real number, why a is in Q[a^3+a]? Q means rationals.
thanks

If a is "constructible" (assuming ruler-and-compass construction is
meant here),
then what can we say about the dimension of Q[a] over Q?

Now Q[a] contains Q[a^3 + a]. What can we say about the "dimension" of
that
(integral) extension?

Some details need to be filled in...

regards, chip

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