An algebra problem by A Former Brilliant Member

Algebra Level 2

∑ x = 1 400 x 3 = ? \large \sum_{x=1}^{400} x^3 = \ ?


The answer is 6432040000.

A Former Brilliant Member by A Former Brilliant Member

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.

1 solution

The sum of the first n n cubes is the square of the sum of the first n n positive integers. Therefore the answer is

[ 400 2 ( 401 ) ] 2 = \left[\dfrac{400}{2}(401)\right]^2= 6432040000 \color{#D61F06}\boxed{6432040000}

0 Helpful 0 Interesting 0 Brilliant 0 Confused

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...