Advertisements
Advertisements
प्रश्न
Prove that `3 - 2sqrt(5)` is an irrational number, given that `sqrt(5)` is an irrational number.
उत्तर
To Prove: `3 - 2sqrt(5)` is an irrational number
Given `sqrt(5)` is an irrational number
Let `3 - 2sqrt(5)` is a rational number
∴ `3 - 2sqrt(5) = p/q` ...(Where q ≠ 0)
`3 - 2sqrt(5)q` = p
3q – p = `2sqrt(5)q`
`(3q - p)/(2q) = sqrt(5)`
p and q of are integers
∴ `(3p - q)/(2q)` is a rational number but `sqrt(5)` is an irrational number
Hence rational number ≠ irrational number
So our assumption is wrong by contradiction fact
∴ `3 - 2sqrt(5)` is an irrational number.
Hence Proved.
APPEARS IN
संबंधित प्रश्न
Classify the numbers 2.040040004 as rational or irrational:
Classify the numbers 3.121221222 as rational or irrational:
Prove that of the numbers ` 2 - sqrt(3)` is irrational:
State whether the given statement is true or false:
1 .The product of two irrationals is an irrational .
Write a pair of irrational numbers whose sum is irrational.
Insert five irrational numbers between `2sqrt5` and `3sqrt3`.
Check whether the square of the following is rational or irrational:
`3 + sqrt(2)`
Prove that `sqrt(p) + sqrt(q)` is irrational, where p, q are primes.
Insert a rational number and an irrational number between the following:
6.375289 and 6.375738
Prove that `(2-sqrt3)/5` is an irrational number, given that `sqrt 3` is an irrational number.