Application of Integrals — Class 12 Maths Solution

exemplar la LA NCERT Exemp. Ex. 1.3, Q. 17, Page 177
Question

Find the area bounded by the curve $y = \sin x$ between $x = 0$ and $x = 2\pi$.

Step-by-step Solution

As per the given figure, we need to find the area of the region :

OABCD = Ar.(OAB)+Ar.(BCD)

Let us find the area of OAB first :

= $\int^{\pi}_0 sinx dx$
$= [-cosx]^{\pi}_0$

$= -[cos\pi - cos0]= -[-1-1]=2$

Now let us find the area of BCD
=$\int^{2\pi}_{\pi}sinxdx$

$=-[cosx]^{2\pi}_{\pi}$
$=-[1-(-1)]= -2$

as we know that area can't be negative therefore area of BCD = 2

Hence area of OAB +BCD = 2+2=4

Hence the required area = 4 sq units

NCERT & Exemplar solution for CBSE Class 12 Mathematics, Application of Integrals. Curated by Sachin Sharma. Free for all students.