Area of a sector IB Maths SL

Algebra, Functions and equations, Circular functions and trigonometry, Vectors, Statistics and probability, Calculus. IB Maths SL Revision Notes

Area of a sector IB Maths SL

IB Mathematics HL– Trigonometry, Mensuration, Area of a sector

How can we find the area of sector with central angle $\frac{\pi}{6}$ in a circle with radius 7 cm?

Thanks
Jane

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Joined: Tue Mar 19, 2013 8:47 pm

Re: Area of a sector IB Maths SL

IB Maths HL – Trigonometry, Mensuration, Area of a sector

Let $\theta$ (in radians) be the central angle in a circle with radius r, then the area $A$ of the sector formed by angle $\theta$ is given by the following formula:

$A=\frac{1}{2}r^2 \theta$

Therefore the arc length in our case is

$A=\frac{1}{2}(7)^2 \frac{\pi}{6} =\frac{49\pi}{12} cm^2$

Hope these help!!
miranda

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Joined: Mon Jan 28, 2013 8:03 pm

Re: Area of a sector IB Maths SL

Thanks a lot!
Jane

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Joined: Tue Mar 19, 2013 8:47 pm