Question

Prove that 2 -3 √5

is an irrational number.

Answer 1

Answer:

2 -3root 5= a/b

-3root 5= a-2÷b

-3root5= a-2÷b

root5 = a-2b÷3b

irrational = rational

here L.h.s is an rational but R.h.s is a rational number

so this contradict our assumption