Question

can anyone tell me the answer i will it as brilliant..

question no. 1​

Answer 1

Answer:

Step-by-step explanation:

Provided √5 is irrational

Let us prove by  contradiction method

Let us assume (4 + √5) is rational ,then there exists two unique integers

a and b such that 4 +√5 = a/b ( where a and b are co primes and b≠0)

4 + √5 = a/b

⇒√5 =     a - 4b /b     ( taking lcm)

a - 4b / b is a rational number therefore LHS = RHS and √5 is rational

But this is a contradiction since √5 is irrational

∴Our assumption is wrong and 4 + √5 is irrational