# Science:Math Exam Resources/Courses/MATH103/April 2015/Question 03 (a)

MATH103 April 2015
Other MATH103 Exams

### Question 03 (a)

The equation of a circle of radius ${\displaystyle r}$ centred at the origin is ${\displaystyle x^{2}+y^{2}=r^{2}}$.

(a) The area A of the circle is given by ${\displaystyle A=2\int _{-r}^{r}{\sqrt {r^{2}-x^{2}}}dx.}$

Draw a sketch, which clearly identifies the integrand, and shade the area given by ${\displaystyle \int _{-r}^{r}{\sqrt {r^{2}-x^{2}}}dx.}$

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