Question | Check whether 6n can end with the digit 0 for any natural number n. |
Board | CBSE |
Textbook | NCERT |
Class | Class 10 |
Subject | Maths |
Chapter | Chapter 1 Real Numbers |
Question – Check whether 6n can end with the digit 0 for any natural number n.
Solution:Â Â Given : 6n
To find: Whether 6n end with 0 or not.
We know that any number which is multiplied by 5 or 10, or multiples of 10 end with 0.
Let 6n can end with the digit 0. Then 5 must be a prime factor of it.
Now, 6n = (2 Ă— 3)n, i.e., 2 and 3 are the only prime factors, which is a contradiction to the fact that 5 is a prime factor of 6n.
Hence our assumption is wrong.
Therefore, 6n can not end with the digit 0 for any natural number n.
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