show that 3+2root 5is an irrational number
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Answer = let us assume the opposite ,
.i.e,3+2√5 is rational
Hense, 3+2√5 canbe written in the form of a/b
where a and b (b≠0) are co prime (no commen factor othet than 1)
Hense, 3+2√5=a/b
2√5= a/b-3
2√5=a-3b/b
√5 =1/2 X a-3b/b
√5=a-3b/2b
Here=a-3b/2b is a Rational number
but √5 is irrational
sinse rational ≠irrational
this is a contradiction
our assumption is incorrect
Hense 3+2√5 is irrational
Hense proved
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