Thread: real number problem 2

prove that if a positive integer is of the form 6q + 5 then it is in the form 3 q + 2 for some integer q but not conversely.

Originally Posted by saha.subham

prove that if a positive integer is of the form 6q + 5 then it is in the form 3 q + 2 for some integer q but not conversely.

This one is easy.
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The number 2 is the counterexample needed in the second part.

plzz explain a bit more the part two

Originally Posted by saha.subham

plzz explain a bit more the part two

2=3.0+2, so it is of the form 3q+2 (take q=0).

2 is not of the form 6q+5.
If it were, then
2=6q+5
3=6q
q=-1/2, which is not an integer.