Question

What is the sum of the squares ofthe first 20 natural numbers (1 to 20)?

Answer 1

Answer:

2730

Step-by-step explanation:

1²+2²+3²+······················n²=[n(n+1)(2n-1)]/6 where n is any number till which the sum must be found.

to find:

1²+2²+3²+................+19²+20²

∴n=20

by using the above formula,

[20(20+1)(2(20)-1)]/6

[20(21)(39)]/6

16380/6

2730