Question

Prove that √5 is an irrational number.​

Answer 1

Answer: b√a=a

squaring both sides

(b√5)^=a^

5b^=a^

5 divides a^

so, a=5c

5b^=a^

5b^=(5c)^

5b^=25c^

b^=c^

b^=5c^

i. e, 5c^=b^

5÷b^

from the equation

√5 is irrational number.