What is the integer part of the value of the expression x = 1 / (√121 - √120)?
Show answer & explanation
Correct answer: C
Explanation
Given:
x = 1 / (√121 − √120)
By the formula:
1 / (a − b) = (a + b) / (a² − b²)
x = 1 / (√121 − √120)
= (√121 + √120) / (121 − 120)
= √121 + √120
= 11 + √120
√120 ≈ 10.95
x ≈ 11 + 10.95
x ≈ 21.95
Integer part = 21