Problem for the next perfect sqare year!

Algebra Level 3

3 ( 1 2 + 4 2 + 9 2 + 1 6 2 + + 202 5 2 ) 2 + 2 ( 1 2 + 4 2 + 9 2 + 1 6 2 + + 202 5 2 ) + 1 \begin{aligned} && 3(1^{2}+4^{2}+9^{2}+16^{2}+\ldots+2025^{2})^{2} \\&&+2(1^{2}+4^{2}+9^{2}+16^{2}+\ldots+2025^{2})+1 \end{aligned} Find the remainder when the number above is divided by ( 4 2 + 9 2 + 1 6 2 + + 202 5 2 ) (4^{2}+9^{2}+16^{2}+\ldots +2025^{2}) .


The answer is 6.

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

2 solutions

Let ( 1 2 + 4 2 + 9 2 + 1 6 2 + . . . + 202 5 2 ) = x (1^{2}+4^{2}+9^{2}+16^{2}+...+2025^{2})=x . Therefore we want to know the remainder of 3 x 2 + 2 x + 1 x 1 \dfrac{3x^{2}+2x+1}{x-1} . By remainder theorem what we want to know is 3 ( 1 ) 2 + 2 ( 1 ) + 1 = 6 3(1)^{2}+2(1)+1=6

Moderator note:

Yes. Because 4 2 + 9 2 + 1 6 2 + . . . + 202 5 2 4^{2}+9^{2}+16^{2}+...+2025^{2} pops up everywhere. It might be useful to consider a symbol to represent it. Thus making it so much simpler.

I did not see 1 at the 'end':)

Vincent Miller Moral - 5 years, 9 months ago
Lu Ca
Jun 26, 2019

Let 4 2 + 9 2 + 1 6 2 + . . . 202 5 2 = n 4^2+9^2+16^2+...2025^2=n then 3 ( 1 2 + 4 2 + 9 2 + 1 6 2 + . . . 202 5 2 ) 2 + 2 ( 1 2 + 4 2 + 9 2 + 1 6 2 + . . . 202 5 2 ) + 1 = 3 ( 1 + n ) 2 + 2 ( 1 + n ) + 1 = 3 n 2 + 8 n + 6 = ( 3 n + 8 ) n + 6 3(1^2+4^2+9^2+16^2+...2025^2)^2+2(1^2+4^2+9^2+16^2+...2025^2)+1=3(1+n)^2+2(1+n)+1=3n^2+8n+6=(3n+8)n+6 , so 3n+8 is the quotient and 6 is the remainder.

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...