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प्रश्न
If some or all of n objects are taken at a time, the number of combinations is 2n – 1.
विकल्प
True
False
उत्तर
This statement is True.
Explanation:
When some or all objects, taken at a time, then the number of selection will be
nC1 + nC2 + nC3 + ... + nCn
= 2n – 1 .....[∵ nC0 + nC1 + nC2 + ... + nCn = 2n]
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