Osion kaavat

[[$ A=a \cdot h $]]​	[[$ A=\frac{a \cdot h }{2} $]]​	[[$ A=\frac{(a+b) \cdot h}{2} $]]​	[[$ a^2+b^2=c^2 $]]​
[[$ \pi = \frac{p}{d} $]]​	[[$ p=\pi \cdot d $]]​	[[$ p = 2 \pi r $]]​
[[$ A=\pi r^2 $]]​	[[$ b = \frac{\alpha}{360^{\circ}} \cdot 2\pi r $]]​	[[$ A = \frac{\alpha}{360^{\circ}} \cdot \pi r^2 $]]​