The rectangle is inscribed in a circle with Dia = 10 cm. The area of the segment that is formed by the shorter side of the rectangle and the circumference of a circle is 4 cm2. Find the area of that rectangle.
Hello Guest!
\(\alpha\) = center angle
r = radius
s = chord
b = long side of the rectangle
A = segment area
\(A_R\) = rectangle area
\(\color{blue}A=\frac{r^2}{2}(\alpha -sin \alpha )\\ \alpha -sin \alpha=\frac{2\cdot A}{r^2}=\frac{8cm^2}{(5cm)^2}\\ \alpha -sin\ \alpha=0.32\\ \alpha -sin\ \alpha -0.32=0 \)
http://www.arndt-bruenner.de/mathe/scripts/gleichungssysteme2.htm
Solution found in 1st run after 3 iterations
\(\alpha = 1,27721309204\)
\(s=2r\cdot sin(\frac{\alpha}{2})\\ s=2\cdot 5cm\cdot sin(\frac{1.27721309204}{2})\\ \color{blue}s=5.961cm\)
\(cos(\frac{\alpha}{2})=\frac{\frac{b}{2}}{r}\\ b=2r\cdot cos(\frac{\alpha}{2})=10cm\cdot cos(\frac{1,27721309204}{2})\)
\(b=8.029cm\)
\(A_R=s\cdot b=5.961cm\cdot 8.029cm\)
\(A_R=47.862\ cm^2\)
!
asinus