shubhamsrg
Show that if p and p + 2 with p ≥ 5, are both primes then
the number p + 1 is always divisible by 6.



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shubhamsrg
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p and p+2 are surely odd,, thus p+1 is even > hence p+1 is always divisible by 2.
we now need to prove p+1 is also divisible by 3..am stuck there..

mathslover
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p + 1 is even right?

shubhamsrg
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yep..

mathslover
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hmn wait

shubhamsrg
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yes..maybe even i made a breakthrough,,i shall just post something..

Herp_Derp
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p is either equivalent to 1 mod 3 or 2 mod 3.
then p+2 is the other one.
So p+1 must be 0 mod 3

shubhamsrg
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exactly what i was going to post.. :D

shubhamsrg
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thank you buddies :)

mathslover
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:) welcome though I didn't help

shubhamsrg
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well you gave my question time..thats not a small thing! ;)

mathslover
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You made me feel proud haha