I'm a complete beginner at these:
Could someone please correct me if I'm wrong please (and show me where)....
Here goes:
(3n+1)^3 = (3n)^3 + 3(3n)^2 + 3(3n)^2 + 1
which would give me
= 3 (9n^3 + 6n^2) +1 is this correct?
Originally Posted by Natasha
$\displaystyle (3n+1)^3 = (3n)^3 + 3(3n)^2 + 3(3n)1^2 + 1$
$\displaystyle (3n+1)^3 = (3n)^3 + 3(3n)^2 + 3(3n) + 1$
I have marked with red ^2 in your post because in theorem its b^2 and because b=1 then b^2 =1, you have put (ab)^2 or a^2.