Prove that `(2sqrt(3))/5` is irrational.

Explanation

Let us assume that 2 sqrt3 +sqrt5 is rational number

Let `p/q=(2 sqrt3) /5` is rational number

Multiplying 5/2 on both side we get,

`p/q xx 5/2 = (2 sqrt3) /5 xx5/2`

`:. (5p)/(2q) = sqrt3`

As we know` p/q` is rational number

`:. (5p)/(2q)` is also rational number

But sqrt3 is not a rational number

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