Prove sq root of 2 + sq root of 3 is irrational

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The discussion focuses on proving that the sum of the square roots of 2 and 3 is irrational. The user attempts to apply a proof by contradiction, starting with the assumption that √2 + √3 can be expressed as a rational number p/q. The key steps involve manipulating the equation to show that this leads to the conclusion that √6 must also be rational, which contradicts the established fact that √6 is irrational. Thus, the proof confirms that the sum of a rational and an irrational number remains irrational.

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yanjt
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hi,i read the post of sq root of 2 + sq root of 3.i understand tat i should use contradiction to solve it.yet,i stuck halfway when i tried to solve it.
sq root 2 + sq root 3 = p/q
2 + 2*sq root 6 +3=p^2/q^2
5+2*sq root 6 = p^2/q^2
wat should i do after this?i have to prove that the addition of a raitonal and irrational number is irrational?
 
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yanjt said:
hi,i read the post of sq root of 2 + sq root of 3.i understand tat i should use contradiction to solve it.yet,i stuck halfway when i tried to solve it.
sq root 2 + sq root 3 = p/q
2 + 2*sq root 6 +3=p^2/q^2
5+2*sq root 6 = p^2/q^2


Rearrange, and you see that you have to show that sqrt(6) is rational: rational plus rational is rational


wat should i do after this?i have to prove that the addition of a raitonal and irrational number is irrational?

See above.
 

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