Question

Prove that 2-3√5 is
irrational no.​

Answer 1

Assume 2-3√5 be a rational no

therefore 2-3√5=a/b

hence √5=a-2b/3b

therefore a-2b/3b is a rational no

therefore √5 is a rational no

but we know that √5 is a irrational no

therefore our assumption was wrong that 2-3√5 is a rational no

therefore 2-3√5 is a irrational no

Answer 2

Answer:

First prove that square root of 5 is an irrational number.Then take 2-3*square root of 5 as a rational number.find the value in terms of square root of 5,and then by your assumption,square root of 5 is a rational number.but it contradicts the fact that it is an irrational number.so,2-3*square root of 5 is an irrational number.

Step-by-step explanation: