Question 764886
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{{{(sqrt(2) - sqrt(3))*(sqrt(2) + sqrt(3))}}}

applying the identity (a+b)*(a-b) = a^2 - b^2

= {{{(sqrt(2))^2 - (sqrt(3))^2}}}

= {{{ 2 - 3 = -1}}}

Hence the expression is a rational.

:)
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