Prove the √5is irrational number hence show that 3+√5 is also irrational
Answers
root5 has no common factor so assume that root5is rational and p/q has no common factir
root5=p/q
squaring on both sides
(root5)²=(p/q)²
5=p²/q²
5q²=p²
so 5 is a factor of p²
also 5 is a factor of p
let p=5m
5q²=(5m)²
5q²=25m²
q²=5m²
so 5 is a factor of q²
also 5 is a factor of q
Hence we said that root5 is rational but according to our contradiction root5is irrational.
3+root5=k
root5 =k-3
LHS is irrational we know that and also RHS is irrational so 3+root5 is irrational
Step-by-step explanation: