JEE Main2014MathematicsDefinite IntegrationActual
If [ ] denotes the greatest integer function, then the integral ₀^ [ x d x is equal to:
Options
- A2
- B0
- C-1
- D- 2
Correct answer
D. - 2
Step-by-step solution
Let I = ₀^ [ x] d x I = ₀^ [ ( -x)] d x= ₀^ [- x] d x On adding (1) and (2), we get aligned &2 I = ₀^ [ x] d x+ ₀^ [- x] d x &2 I = ₀^ [ x]+[- x] d x &2 I &= ₀^ -1 d x ( [x]+[-x]=-1 if x Z) &2 I =- .x |₀ ^ =- & I = - 2 aligned