Which one of the following is the difference of the sum of cubes of fi

Which one of the following is the difference of the sum of cubes of first ten natural numbers and the sum of squares of first ten natural numbers?

2400
2640
2880
2000
This question was previously asked in
UPSC CAPF – 2022
The sum of the first ten natural numbers’ cubes is calculated using the formula $[\frac{n(n+1)}{2}]^2$ with n=10, giving $[\frac{10(11)}{2}]^2 = 55^2 = 3025$. The sum of the first ten natural numbers’ squares is calculated using the formula $\frac{n(n+1)(2n+1)}{6}$ with n=10, giving $\frac{10(11)(21)}{6} = \frac{2310}{6} = 385$. The difference is $3025 – 385 = 2640$.
The problem requires knowing the formulas for the sum of cubes and the sum of squares of the first ‘n’ natural numbers and applying them for n=10.
The formula for the sum of the first n natural numbers is $\frac{n(n+1)}{2}$. The sum of cubes of the first n natural numbers is the square of the sum of the first n natural numbers: $(\sum_{k=1}^n k)^2 = (\frac{n(n+1)}{2})^2$. The sum of squares of the first n natural numbers is $\sum_{k=1}^n k^2 = \frac{n(n+1)(2n+1)}{6}$.
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