Let ustake a point S on one end of the given figure. Rotating by 180°, S comes atother end and then again rotating by 180°, it comes at its original position.
∴ Orderof rotational symmetry = 360∘/180∘=2
Let ustake any point S in figure (1). It takes two rotations to come back to itsoriginal position.
∴ Orderof rotational symmetry = 360∘/180∘=2
Let us mark any vertex of the given figure. It takes three rotations to comeback to its original shape.
∴ Orderof rotational symmetry = 360∘/120∘=3
Orderof rotational symmetry = 360∘/90∘=4
∴ Orderof rotational symmetry = 360∘/90∘=4
(f)The given figure is a regular pentagon which can take one rotation at an angleof 72°.
∴ Orderof rotational symmetry = 360∘/72∘=5
(g) The given figure requires six rotations each through an angle of 60°
∴ Orderof rotational symmetry = 360∘/60∘=6
(h)The given figure requires three rotations, each through an angle of 120°.
∴ Orderof rotational symmetry = 360∘/120∘=3