Verify by the method of contradiction. `p:sqrt(7)`is irrational.

Explanation

Let us assume `p:sqrt7` is a rational.

`=>sqrt7 = a/b`

It means, ,`a` and `b` have no common factor.

Also, `a^2/b^2 = 7=> a^2 = 7b^2->(1)`

Above equation means, `a^2 ` has a factor of `7`.

So, `a` will also have a factor of `7`.
We can also write it as,

`a = 7c->(2)` where `c` is another real number.

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