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Question
If xn – 1 is divisible by x – k, then the least positive integral value of k is ______.
Options
1
2
3
4
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Solution
If xn – 1 is divisible by x – k, then the least positive integral value of k is 1.
Explanation:
Let P(n) = xn – 1 is divisible by x – k.
P(1) = x – 1 is divisible by x – k.
Since k = 1 is the possible least integral value of k.
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