Is (2^1/2 + 7^1/3)^1/2 irrational?

Thread starter trap101
Start date Feb 14, 2012
Tags

Irrational

Feb 14, 2012

trap101

Hi,

So I proved that 7^1/3 is irrational, and I know 2^1/2 is irrational, but how can I show if (2^1/2 + 7^1/3)^1/2 is irrational?

Hint of where to start?

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Feb 14, 2012

trap101

Never mind, figured it out.

Feb 14, 2012

checkitagain

trap101 said:

Never mind, figured it out.

Can you give a summary as to how you figured it out?

I was working on it after you posted it.

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