Question 212504: sequence 4,7,10,....
formula 3n+1
if two numbers of the sequence are multiplied need to show proof that result is always a number in this sequence.
please give guidance
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! sequence 4,7,10,....
formula 3n+1
if two numbers of the sequence are multiplied need to show proof that result is always a number in this sequence.
---------------------
You need to show that if two numbers having that form are multiplied
the product has that form.
------------------------------
1st number 3a + 1
2nd number 3b + 1
------------------------
Product: 9ab + 3a + 3b + 1
Rearrange:
3(3ab+a+b) + 1
It has the form 3k+1
That proves what you were asked to prove.
=============================
Cheers,
Stan H.
-----------------------
|
|
|
