1/(9 + √6) + 1/(9 − √6) = ?
Show answer & explanation
Correct answer: C
Explanation
Given:
1/(9 + √6) + 1/(9 − √6)
Using the formula:
1/(a + b) + 1/(a − b) = 2a/(a² − b²)
= (2 × 9) / (9² − (√6)²)
= 18 / (81 − 6)
= 18 / 75
= 6 / 25
SSC MTS - 12 Feb 2026 - Shift 3 • Quantitative Aptitude • Q11
1/(9 + √6) + 1/(9 − √6) = ?
Correct answer: C
Explanation
Given:
1/(9 + √6) + 1/(9 − √6)
Using the formula:
1/(a + b) + 1/(a − b) = 2a/(a² − b²)
= (2 × 9) / (9² − (√6)²)
= 18 / (81 − 6)
= 18 / 75
= 6 / 25