Let r=p1/q 1is a rationale number and s is irrational.
We have to prove that r+s is irrational number.
Suppose r+s is rational
Then;
r+s= p/q
p1/q1+s=p/q
s=p/q-p1/q1= (pq1-p1q)/qp1=p2/q2
This is contradiction because it is given that s is irrational. So our supposition is wrong.
Hence r+s is irrational.
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