Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section A

Chapter

Definite Integration

Question:

Value of $\int\limits_0^n[x] d x$ (where n ∈ N) is

Options:

$\frac{n(n+1)}{2}$

$\frac{n(n-1)}{2}$

$n(n-1)$

None of these

Correct Answer:

$\frac{n(n-1)}{2}$

Explanation:

$\int\limits_0^n[x] d x=\sum\limits_{i=1}^n \int\limits_{i-1}^i[x] d x$

$\sum\limits_{i=1}^n(i-1) d x=\frac{n(n-1)}{2}$

Hence (2) is the correct answer.