Important Formulae: Shapes | Mathematics & Pedagogy Paper 1 for CTET & TET Exams - CTET & State TET PDF Download

Shapes

• 2D Shapes (Plane Shapes):

  • Triangle: 3 sides and 3 corners.
  • Square: 4 equal sides and 4 corners.
  • Rectangle: 4 sides with opposite sides equal.
  • Circle: No corners or sides, a closed curve.
  • Oval: No corners or sides, a closed curve.

• 3D Shapes (Solid Shapes):

  • Cube: 6 faces, 12 edges, all faces equal.
  • Cuboid: 6 faces, 12 edges, opposite faces equal.
  • Sphere: 1 face, 0 edges, 0 corners.
  • Cone: 2 faces, 1 edge, 1 corner.
  • Cylinder: 3 faces, 2 edges, 0 corners.

Point and Lines

• Point: A dot, has no shape or dimensions, named with a capital letter.
• Straight and Curved Lines: Formed by connecting points; straight lines do not intersect, curved lines may intersect.

Circle

• Circle: A closed curve where all points are equidistant from the center.

• Terms Related to Circle:

  • Centre: Fixed point in the middle of the circle.
  • Diameter: Line segment passing through the center with endpoints on the circle.
  • Radius: Distance from the center to any point on the circumference.
  • Chord: Line segment with endpoints on the circle.
  • Arc: Part of a circle, named by its endpoints.
  • Circumference: Perimeter of the circle, C = π × diameter or 2 × π × radius.
  • Semicircle: Half of a circle, a special type of arc.
  • Interior and Exterior: Points inside, outside, and on the circle.
  • Concentric Circles: Circles with the same center but different radii.

• Drawing a Circle with Compass:

  1. Fix a pointed pencil in the compass.
  2. Place the metal tip at the center point 'O'.
  3. Set the compass to the desired radius length (e.g., 3 cm).
  4. Draw the circle by rotating the compass around point 'O'.

Spatial Understanding

• Spatial Concepts:

  • Position: Near, far, above, below.
  • Direction: Left, right, up, down.
  • Movement: Understanding movement and direction.
  • Symmetry: Recognizing patterns and symmetry.