Advertisements
Advertisements
Question
Prove that \[2 - 3\sqrt{5}\] is an irrational number.
Solution
Let us assume that \[2 - 3\sqrt{5}\] is rational .Then, there exist positive co primes a and b such that
`2-3sqrt5=a/b`
`3sqrt5=a/b-2`
`3sqrt5=(a/b-2)/3`
`sqrt5=(a-2b)/(3b)`
This contradicts the fact sqrt5 is an irrational number
Hence `2-3sqrt5` is irrational
APPEARS IN
RELATED QUESTIONS
Prove that the product of two consecutive positive integers is divisible by 2.
Show that every positive even integer is of the form (6m+1) or (6m+3) or (6m+5)where m is some integer.
Using prime factorization, find the HCF and LCM of 144, 198 In case verify that HCF × LCM = product of given numbers.
Express each of the following as a rational number in its simplest form:
(i) `2. bar (24)`
What do you mean by Euclid’s division algorithm.
What is the smallest number that, when divided by 35, 56 and 91 leaves remainders of 7 in each case?
Prove that \[\sqrt{5} + \sqrt{3}\] is irrational.
If a = 23 ✕ 3, b = 2 ✕ 3 ✕ 5, c = 3n ✕ 5 and LCM (a, b, c) = 23 ✕ 32 ✕ 5, then n =
If HCF (16, y) = 8 and LCM (16, y) = 48, then the value of y is ______.
The LCM of two prime numbers p and q (p > q) is 221. Find the value of 3p - q.