S MDHS MHF4U AM Name: _______________________ Knowledge Application /10 /14 Thinking 19 Communication /9 /7 Unit 4 Test - Trigonometric Equations Knowledge [ /10] 14/9 1. Convert the 140 to radians. _______ 𝑜 2. Convert 10π 9 [1] 2000 to degrees ________ [1] 3. How many possible solutions exist for 𝑠𝑖𝑛3𝑥 = −1 2 6 in the interval 0 ≤ 𝑥 ≤ 2π? _________ [1] D [1] 4. How many possible solutions exist for 𝑐𝑜𝑠𝑥 = 3 ? ___________ 2 [1] O T 5. Determine all solutions for 𝑠𝑖𝑛𝑥 = 0 in the interval 0 ≤ 𝑥 ≤ 2π ________________ , , I [1] ( ) + 𝑠𝑖𝑛 ( ) ______________ 2 2π 15 6. Evaluate the following using exact values: 𝑐𝑜𝑠 2 2π 15 7. Determine the exact value for each of the following: [2, 2] 3π a) 𝑐𝑜𝑠 4 A =- T cos(*( + ) I g π 6 b) 𝑐𝑠𝑐 = Sin/6 = = 1 = 2 t # Application [ /14] 8. Given 𝑡𝑎𝑛𝐴 = 7 4 2 where π < 𝐴 < 3π 2 : a) Sketch the angle and determine the missing side length. [2] A S p2 72442 = 49 + 16 = r= y 5 b) Determine the exact value of 𝑠𝑖𝑛2𝐴 [3] - = = = 2 Sin x cost ~ - 2()( S ~ S 9. Solve the following equations for when 0 ≤ 𝑥 ≤ 2π a) 2𝑐𝑜𝑠𝑥 + 5 = 4 10. Choose one of the two identities to prove: a) 𝑠𝑖𝑛𝑥 − 𝑡𝑎𝑛𝑦𝑐𝑜𝑠𝑥 = 𝑠𝑖𝑛(𝑥−𝑦) 𝑐𝑜𝑠𝑦 [4, 6] b) 6𝑠𝑖𝑛2𝑥 = 3 [4] 4 b) 4 𝑐𝑜𝑠 𝑥−𝑠𝑖𝑛 𝑥 2 𝑠𝑖𝑛 𝑥 2 = 𝑐𝑜𝑡 𝑥 − 1 Thinking [ /9] 11. Solve 𝑐𝑜𝑠2𝑥 − 3𝑠𝑖𝑛𝑥 − 2 = 0 when 0 ≤ 𝑥 ≤ 2π [5] 12. Choose one of the two identities to prove: [4] 2 a) 2𝑠𝑖𝑛 𝑥(1 + 𝑐𝑜𝑡𝑥) = 𝑠𝑖𝑛2𝑥 − 𝑐𝑜𝑠2𝑥 + 1 b) 𝑠𝑖𝑛2𝑥 2 2−2𝑐𝑜𝑠 𝑥 = 2𝑐𝑠𝑐2𝑥 − 𝑡𝑎𝑛𝑥 Communication [ /7] 13. A student thinks that 𝑠𝑖𝑛θ = 1 − 𝑐𝑜𝑠θ is an identity because 𝑠𝑖𝑛(0) = 1 − 𝑐𝑜𝑠(0) = 0. Is this true or false? If false, provide a counterexample. [2] Communication /5 - Form (equal signs, working down, proper “let” statements, therefore statements, etc) - Grammar and Spelling (where applicable) Trigonometric Identities RECIPROCAL IDENTITIES: PYTHAGOREAN IDENTITIES: Compound Angle Identities 𝑡𝑎𝑛(𝐴 − 𝐵) = QUOTIENT IDENTITIES: Double Angle Identities 𝑡𝑎𝑛𝐴−𝑡𝑎𝑛𝐵 1+𝑡𝑎𝑛𝐴𝑡𝑎𝑛𝐵