7-6√5 prove that its irrational

1.	7-6√5 prove that its irrational
Answer» Let 7-6√5 as rational. It can be expressed in the form of p/q where p and q are co prime integers.7-6√5=p/q6√5=7-p/q√5=7q-p/6Now since p and q are integers.So RHS is rational so LHS is also rationalBut we know that √5 is irrational This contradiction arises due to our incorrect assumption. This shows our assumption is wrong.So 7-6√5 is irrational. Hence proved :-)

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