Topic 3: Geometry and Trigonometry SL 3.1 Mensuration ● ● ● SL 3.2 SL 3.3 Sine Rule and Cosine Rule Applications of Trigonometry ● The distance between two points in three- dimensional space, and their midpoint. Volume and surface area of three-dimensional solids including right-pyramid, right cone, sphere, hemisphere and combinations of these solids. The size of an angle between two intersecting lines or between a line and a plane. ● Use of sine, cosine and tangent ratios to find the sides and angles of right-angled triangles. 𝑎 𝑏 𝑐 The sine rule: 𝑠𝑖𝑛 𝐴 = 𝑠𝑖𝑛 𝐵 = 𝑠𝑖𝑛 𝐶 . ● The cosine rule: 𝑐 = 𝑎 + 𝑏 − 2𝑎𝑏 𝑐𝑜𝑠 𝐶; 𝑐𝑜𝑠 𝐶 = 2 2 1 2 2 2 2 2 𝑎 +𝑏 −𝑐 2𝑎𝑏 ● Area of a triangle as ● Applications of right and non-right angled trigonometry, including Pythagoras’ theorem. Angles of elevation and depression. Construction of labelled diagrams from written statements. ● ● . 𝑎𝑏 𝑠𝑖𝑛 𝐶. SL 3.4 The Unit Circle ● The circle: radian measure of angles; length of an arc; area of a sector. SL 3.5 Trigonometry with Radian Measurement ● ● Definition of 𝑐𝑜𝑠 θ, 𝑠𝑖𝑛 θ in terms of the unit circle. 𝑠𝑖𝑛 θ Definition of 𝑡𝑎𝑛 θ as 𝑐𝑜𝑠 θ . ● Exact values of trigonometric ratios of ● multiples. Extension of the sine rule to the ambiguous case. π 6 , π 4 , π 3 , π 2 and their SL 3.6 Trigonometric Identities ● ● SL 3.7 Trigonometric Functions and Transformations ● ● ● ● SL 3.8 Trigonometric Equations ● ● AHL 3.9 Reciprocal Trigonometric Ratios ● ● 2 2 The Pythagorean identity 𝑐𝑜𝑠 θ + 𝑠𝑖𝑛 θ = 1. Double angle identities for sine and cosine. The relationship between trigonometric ratios. The circular functions 𝑠𝑖𝑛 𝑥, 𝑐𝑜𝑠 𝑥, and 𝑡𝑎𝑛 𝑥; amplitude, their periodic nature, and their graphs. Composite functions of the form 𝑓(𝑥) = 𝑎 𝑠𝑖𝑛 (𝑏(𝑥 + 𝑐)) + 𝑑. Transformations. Real-life contexts. Solving trigonometric equations in a finite interval, both graphically and analytically. Equations leading to quadratic equations in 𝑠𝑖𝑛 𝑥, 𝑐𝑜𝑠 𝑥 or 𝑡𝑎𝑛 𝑥. Definition of the reciprocal trigonometric ratios 𝑠𝑒𝑐 θ, 𝑐𝑠𝑐 θ and 𝑐𝑜𝑡 θ. Pythagorean identities: 2 2 2 2 ○ 1 + 𝑡𝑎𝑛 θ = 𝑠𝑒𝑐 θ ○ ○ 1 + 𝑐𝑜𝑡 θ = 𝑐𝑠𝑐 θ The inverse functions 𝑓(𝑥) = 𝑎𝑟𝑐𝑠𝑖𝑛 𝑥, 𝑓(𝑥) = 𝑎𝑟𝑐𝑐𝑜𝑠 𝑥, 𝑓(𝑥) = 𝑎𝑟𝑐𝑡𝑎𝑛 𝑥; their domains and ranges; their graphs. AHL 3.10 Compound Angle Identities ● ● Compound angle identities. Double angle identity for 𝑡𝑎𝑛. AHL 3.11 Symmetric Properties of Trigonometric Function ● Relationships between trigonometric functions and the symmetry properties of their graphs. AHL 3.12 Vectors ● ● ● Concept of a vector; position vectors; displacement vectors. Representation of vectors using directed line segments. Base vectors 𝑖, 𝑗, 𝑘. ● Components of a vector: 𝑣 =< 𝑣1, 𝑣2, 𝑣3 >= 𝑣1𝑖 + 𝑣2𝑗 + 𝑣3𝑘. ● Algebraic and geometric approaches to the following: ○ the sum and difference of two vectors. ○ the zero vector 0, the vector − 𝑣. ○ multiplication by a scalar, 𝑘𝑣, parallel vectors. 𝑣 ○ magnitude of a vector, |𝑣|; unit vectors, |𝑣| . ○ → → position vectors 𝑂𝐴 = 𝑎, 𝑂𝐵 = 𝑏. → ● ○ displacement vector 𝐴𝐵 =− 𝑏𝑎. Proofs of geometrical properties using vectors. AHL 3.13 Relationships between Vectors ● ● ● The definition of the scalar product of two vectors. The angle between two vectors. Perpendicular vectors; parallel vectors. AHL 3.14 Vector Equation ● Vector equation of a line in two and three dimensions: 𝑟 = 𝑎 + λ𝑏. The angle between two lines. Simple applications to kinematics. ● ● AHL 3.15 Linear Relationships in 3D Space ● ● Coincident, parallel, intersecting and skew lines, distinguishing between these cases. Points of intersection. AHL 3.16 Vector Products ● ● ● The definition of the vector product of two vectors. Properties of the vector product. Geometric interpretation of |𝑣 × 𝑤|. AHL 3.17 Vectors in the Plane ● Vector equations of a plane: ○ 𝑟 = 𝑎 + λ𝑏 + µ𝑐, where 𝑏 and 𝑐 are non-parallel vectors within the plane. ○ 𝑟 · 𝑛 = 𝑎 · 𝑛, where 𝑛 is a normal to the plane and 𝑎 is the position vector of a point on the plane. Cartesian equation of a plane 𝑎𝑥 + 𝑏𝑦 + 𝑐𝑧 = 𝑑. ● AHL 3.18 Intersections between Lines and Planes ● ● Intersections of: a line with a plane; two planes; three planes. Angle between: a line and a plane; two planes.