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Thus, an object is said to have a rotational symmetry if, after rotation about the centre through
a certain angle, it looks exactly the same as the original position.

Snowflakes also show rotational symmetry of order 6.

60° 120° 180° 240° 300° 360°

Rotational symmetry in Snowflakes.
Every object has a rotational symmetry of order 1 as it looks the same after a complete rotation
of 360°. Such cases have no interest for us.
Example 11: Show the rotational symmetry for the figures given below.

(a) (b) B

A C

Solution: (a)
360°

180°
Initial position After 180° After 360°
rotation rotation

(b) B A C B

120° 120°
B A
A C C B 120° A C
Initial position After 120° After 240° After 360°
rotation rotation rotation
Example 12: In the word “SIGHT” which letters show rotational symmetry?

Solution: The letters are ‘S’, ‘I’, ‘G’, ‘H’ and ‘T’. Among these letters, only the letters S, I and H show
rotational symmetry at the angles of 180° and 360° rotation.

After 90° After 180° After 270° After 360°

After 90° After 180° After 270° After 360°

After 90° After 180° After 270° After 360°

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