Question

prove that 3 minus root 5 is an irrational number​

Answer 1

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3 - √5 be a rational number.

°. 3 + √5 = p/q [ where p and q are integer , q ≠ 0 and q and p are co - prime number ]

=> √5 = p/q - 3

=> √5 = p - 3q/q

we know that p/q is a rational number..°. √5 is also a rational number.

This contradicts our assumption..°.

3 - √5 is an irrational number

Answer 2

Step-by-step explanation:

let 3 -root 5 is rational number... let a and b are two integers.. so we can write this a/b =3 - root 5

now square both sides then a square/ b square= 15 then a square is equal to 15b square we say that a is divisible by 15 then a square is Also divisible by 15... now we take another integer c same process apply it's an end our hyphothetis it's wrong then we can say that 3- root5 is irational number h.p