MEP Practice Book ES Facts to Remember Unit 7 x Square: Area = x 2 x x x w w Rectangle: Area = lw ll Triangle: Area = 1 bh 2 a c hh bb Circle: Area = π r 2 r Parallelogram: Area = bh h Circumference = 2 π r h b b a a 1 Trapezium: Area = ( a + b )h 2 h h b b a a 1 Kite: Area = ab 2 b b a Cube: Volume = a 3 a a b Cuboid: Volume = abc Surface area = 6 a 2 Surface area = 2( ab + bc + ca) c a h 2 Cylinder: Volume = π r h Surface area = 2π r 2 + 2π rh r l Prism: Volume = Al h A b Pyramid: Volume = 1 Ah 3 1 Cone: Volume = πr 2 h 3 h A hh rr Sphere: Volume = Anwar Sir, O/A level Mathematics Teacher 4 3 πr 3 r r Surface area = 4 π r 2 Cell: 01712531475, 01972531475 Color profile: Disabled Composite Default screen BACKGROUND KNOWLEDGE AND GEOMETRIC FACTS/ANH 4 For some shapes we can derive a formula for perimeter. The formulae for the most common shapes are given below: b a w l r r d q° c l square rectangle triangle circle P = 4l P = 2(l + w) P = a+ b+ c C =2¼r or C = ¼d arc µ l = ( 360 )2¼r The length of an arc is a fraction of the circumference of a circle. AREA FORMULAE Shape Figure Rectangle Formula Area = length £ width width length Triangle Area = 12 base £ height height base base Parallelogram Area = base £ height height base a Area = Trapezium or Trapezoid h (a +2 b) £h b Circle Area = ¼r2 r Sector Area = q µ (360 ) £¼r 2 r SURFACE AREA FORMULAE RECTANGULAR PRISM c a Anwar Sir, O/A level Mathematics Teacher Cell: 01712531475, 01972531475 100 95 75 50 25 5 Y:\...\IBBK2_00\015IB200.CDR Fri Jun 25 11:08:39 2004 0 100 95 75 50 25 5 0 cyan A = 2(ab + bc + ac) b black IB_02 Color profile: Disabled Composite Default screen 16 BACKGROUND KNOWLEDGE AND GEOMETRIC FACTS CYLINDER CONE Object Outer surface area Object Outer surface area Hollow cylinder A = 2¼rh (no ends) Open cone A = ¼rs (no base) hollow r h s r hollow A = 2¼rh + ¼r2 (one end) Open can hollow Solid cone r h r A = ¼rs + ¼r2 (solid) s solid A = 2¼rh + 2¼r2 (two ends) Solid cylinder solid SPHERE h r r solid Area, A = 4¼r2 VOLUME FORMULAE Object Figure Solids of uniform cross-section Volume Volume of uniform solid = area of end £ length height end height end height height Pyramids and cones h base base r Volume of a sphere = 43 ¼r3 Spheres Anwar Sir, O/A level Mathematics Teacher Cell: 01712531475, 01972531475 100 95 75 50 25 5 Y:\...\IBBK2_00\016IB200.CDR Fri Jun 25 11:08:48 2004 0 100 95 75 50 25 5 0 cyan Volume of a pyramid or cone = 13 (area of base £ height) black IB_02