Thread: Prove by contradiction

Prove by contradiction that 2^(1/3) is irrational.

I made a=2^(1/3).

a^2= 2^(2/3)

then 2^(2/3)= M^2 because we assume a is rational
N^2
then what do I do

Originally Posted by hebby

Prove by contradiction that 2^(1/3) is irrational.

I made a=2^(1/3).

a^2= 2^(2/3)

then 2^(2/3)= M^2 because we assume a is rational
N^2
then what do I do

Do you know the proof of is irrational?
Go along same lines.

Let . Where
Thus
so =>
Can you complete?

Thanks...I can see the proof now...Merci!..it was quite easy