Skip to main contentSkip to solution

The area (sq.units) bounded by the curve y = sinx, π ≤ x ≤ 2π and the x-axis is

Solution

Correct Option: 2

The curve y=sinxy = \sin x for πx2π\pi \leq x \leq 2\pi lies below the x-axis.

At x=πx = \pi: sin(π)=0\sin(\pi) = 0

At x=3π2x = \frac{3\pi}{2}: sin(3π2)=1\sin(\frac{3\pi}{2}) = -1

At x=2πx = 2\pi: sin(2π)=0\sin(2\pi) = 0


Since the curve is below the x-axis, sinx=sinx|\sin x| = -\sin x in this interval.

Area =π2πsinxdx= \int_{\pi}^{2\pi} |\sin x| \, dx

Area =π2π(sinx)dx= \int_{\pi}^{2\pi} (-\sin x) \, dx


The integral of sinx-\sin x is cosx\cos x.

(sinx)dx=cosx\int (-\sin x) \, dx = \cos x

Applying limits from π\pi to 2π2\pi:

Area =[cosx]π2π= [\cos x]_{\pi}^{2\pi}

Area =cos(2π)cos(π)= \cos(2\pi) - \cos(\pi)

Area =1(1)= 1 - (-1)

Area =2= 2


Therefore, the area bounded by the curve y=sinxy = \sin x and the x-axis for πx2π\pi \leq x \leq 2\pi is 22 square units.

Keyboard Shortcuts

  • Left arrow: Previous question
  • Right arrow: Next question
  • S key: Jump to solution
  • Q key: Jump to question