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Find the value of √30 + √30 + √30 +........

1. 5
2. 3√10
3. 6
4. 7

Correct Option: C

According to question ,we can say that
Let , x = √30 + √30 + √30 +........
On squaring both sides, we have
x² = 30 + √30 + √30 + √30 +........
⇒ x² = 30 + x ⇔ x² - x - 30 = 0
⇒ x² - 6x + 5x - 30 = 0
⇒ x( x - 6 ) + 5( x - 6 ) = 0
⇒ ( x - 6 ) ( x + 5 ) = 0
⇒ x = 6 because x ≠ - 5
Hence , required answer is 6 .