90 likes | 108 Views
Learn the essential concepts of Pythagoras' Theorem, Trigonometry in right-angled triangles, and labeling of sides and angles in triangles. Solve problems in a cuboid and isolate and sketch the required triangle.
E N D
Problems in 3D OCR Stage 9
What you should know • Pythagoras’ Theorem • Trigonometry in right-angled triangles • Labelling of sides & angles in triangles
H C G E F D 8cm A C B A B 5cm Cuboid Calculate AC 4cm 8cm 5cm Consider Triangle ABC
C 8cm 5cm A B Calculate AC AC² = 5² + 8² AC² = 25 + 64 Pythagoras says AC2 = AB2 + BC2 AC² = 89 AC = √89 AC = 9.433…cm AC = 9.43cm
H G E F 4cm D A C 8cm 5cm B Calculate Angle GBC
G 4cm B C 8cm SOH CAH TOA Tan angle GBC = 4 / 8 = 0.5 Tan-1 0.5 = 26.565…º O H Angle GBC = 26. 6º A Consider Triangle GBC
H G E F 4cm D A C 8cm 5cm B Calculate Angle GC 9.43cm
A G 4cm 9.43cm A C 9.43cm G C 4cm SOH CAH TOA Tan angle AGC = 9.43 / 4 Tan-1 (9.43 ÷ 4) = 67.014…º H O Angle AGC = 67.0º A
Wedge A B Angle DBF? DF? E F D C Can make calculations as in a Cuboid Isolate & sketch required triangle