Question

9. Prove that 2 + √5 is an irrational number.​

Answer 1

Answer:

Step-by-step explanation:

Let us assume that 2+root5 is rational

SO,

2+root5 = a/b

Root5 = a/b-2 =a-2b/b

But we know that root5 is irrational

So,

Our assumption was wrong

Therefore, 2+root5 is irrational

Hence proved

Answer 2

Answer:

Hey.... I think this can be ur answer!!

Let us assume that 2+root5 is rational

SO,

2+root5 = a/b

Root5 = a/b-2 =a-2b/b

But we know that root5 is irrational

So,

Our assumption was wrong

Therefore, 2+root5 is irrational

Hence proved

Hope it helps you dear