Question

from the given numbers which is an irrational number?
a) (3+√23)-√23
b) 2-√5
c) √25
d) (2√7)/(7√7)​

Answer 1

Answer:-

Option (b) is your correct answer...

Explanation:-

$a)(3 + \sqrt{23} ) - \sqrt{23} \\ \\ = 3 \: \cancel {+ \sqrt{23} } \: \cancel{ - \sqrt{23} } \\ \\ = 3 \\ \\ \blue{3 \: \: is \: a \: rational \: \: number}$

$b)2 - \sqrt{5} \\ \\ \blue{ \sqrt{5} \: \: is \: \: an \: \: irrational \: \: number}$

$c) \sqrt{25} = \sqrt{5 \times 5} = 5 \\ \\ \blue{5 \: \: is \: \: an \: \: rational \: \: number} \\ \\ d) \frac{2 \: \cancel{ \sqrt{7} }}{7 \: \cancel{ \sqrt{7} } } = \frac{2}{7} \\ \\ \blue{ \frac{2}{7} \: \: is \: \: an \: \: rational \: \: number}$

Answer 2

Answer:

ᴀɴꜱᴡᴇʀ ɪꜱ ʙ . ɪᴛ ɪꜱ ɪʀʀᴀᴛɪᴏɴᴀʟ