Value of √5 + 2√6 - 1/√5

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Value of √5 + 2√6 - 1/√5 - 2√6 is

1. 2√2
2. 0
3. 2√3
4. √5 - 1

Correct Option: B

√5 + 2√6 - 1/√5 - 2√6
= ((√5 + 2√6 x √5 - 2√6 ) - 1)/√5 - 2√6

Apply the formula of Algebra.
( a + b ) x (a - b ) = a² - b²
= (√(5)² - (2√6 )² - 1)/√5 - 2√6
= (√25 - 4 x 6 - 1) /√5 - 2√6
= (√25 - 24 - 1) /√5 - 2√6
= (√ 1 - 1 )/√5 - 2√6
= (1 - 1 )/√5 - 2√6
= 0/√5 - 2√6
= 0