Rotational Symmetry of Cross

Transcript

Rotational Symmetry of CrossLet’s consider a cross To check its Rotational Symmetry, we Mark its end points as 1, 2, 3, 4 Rotate it 90° Rotating a Cross 90° Initial figure 90° + 90° = 180° 180° + 90° = 270° 270° + 90° = 360° Thus, in 1 full turn (i.e 360°) The figure is same as that of initial 4 times So, we say that figure has Rotational Symmetry of order 4 And, Angle of symmetry = (𝟑𝟔𝟎° )/(𝑶𝒓𝒅𝒆𝒓 𝒐𝒇 𝑹𝒐𝒕𝒂𝒕𝒊𝒐𝒏𝒂𝒍 𝑺𝒚𝒎𝒎𝒆𝒕𝒓𝒚) = (360° )/4 = 90° Thus, the figure would be same at angles 90° 90° × 2 = 180° 90° × 3 = 270° 90° × 4 = 360° So, we write Angles of symmetry = 90°, 180°, 270°, 360°