## Quant Question Of The Day: 58

[latexpage]

# Numbers

Which of the following numbers are prime numbers?

A. 2^{208} + 1

B. 2^{210} + 1

C. 2^{205} + 1

1. A and B

2. A and C

3. B and C

4. None of the above .

[latexpage]

Which of the following numbers are prime numbers?

A. 2^{208} + 1

B. 2^{210} + 1

C. 2^{205} + 1

1. A and B

2. A and C

3. B and C

4. None of the above .

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1. A and B

Since none of the above can be written in 6k+1 form (3 missing) it is option 4

Prime no.s are of the form 6k+/-1

Here none of them is of the form of prime no.

Hence option 4

A and C