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Higher. Unit 3 Outcome 4. The wave function and a cos α + a sin α. Lesson 1. Starter. Q1. Solution. 0. 2. ∫. ∫. x. dx +. x. dx. -2. 0. 2. ∫. 2. x. dx. 0. Answer D. Thursday, 02 October 2014. Higher. Unit 3 Outcome 4.
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Higher Unit 3 Outcome 4 The wave function and acos α + asin α Lesson 1 Starter Q1 Solution 0 2 ∫ ∫ x dx + x dx -2 0 2 ∫ 2 x dx 0 Answer D Thursday, 02 October 2014
Higher Unit 3 Outcome 4 The wave function and acos α + asin α Example Write 4 cosx + 3sinx in the form K cos(x-α) 0 ≤ α≥ 360 Find K K = 42 + 32 4 cosx + 3 sinx = K cos(x - α) 0 ≤ α≥ 360 K = √ (42 + 32) = K [cosx cosα + sinxsin α] K = √ (16 + 9) K = √ 25 = K cosx cosα + K sinxsin α K = 5 = K cosαcosx + K sin αsinx Find α Reminder tan = sin α 4 cosx + 3 sinx cos α K sin α K cosα= 4 Cosα is pos tan α = cos α K sin α= 3 K sin α is pos tan α = 3 √ αis therefore in the 1st quadrant since cos and sin both positive √ S A √ 4 α = 36.9 √ 4 cosx + 3 sinx = K cos(x - α) T C 4 cosx + 3 sinx = 5 cos(x – 36.9) y = 5 cos (x – 36.9) Thursday, 02 October 2014
Higher Unit 3 Outcome 4 The wave function and acos α + asin α Write the following in the form K cos (x - α) 0 ≤ α≥ 360 a) y = 10 cos(x – 53.13) a) 6 cosx + 8 sinx b) 5 cosx + 12 sinx b) y = 13 cos(x – 67.38) c) 8 cosx + 15 sinx c) y = 17 cos(x – 61.927) Thursday, 02 October 2014
Higher Unit 3 Outcome 4 The wave function and acos α + asin α Wave Function Page 253 Exercise 1A Q2, Q3, Q4 Extension Wave Function Page 253 Exercise 1B Q1, Q2, Q4 Thursday, 02 October 2014
Higher Unit 3 Outcome 4 The wave function and acos α + asin α Write the following in the form K cos (x - α) 0 ≤ α≥ 360 Exam Standard Question Thursday, 02 October 2014
Express in the form Hint Maths4Scotland Higher Expand ksin(x - a): Equate coefficients: Square and add a is in 1st quadrant (sin and cos are both +) Dividing: Put together: Previous Next Quit Quit
The diagram shows an incomplete graph of Find the coordinates of the maximum stationary point. Hint Maths4Scotland Higher Max for sine occurs Sine takes values between 1 and -1 Max value of sine function: Max value of function: 3 Coordinates of max s.p. Previous Next Quit Quit
a) Express f (x) in the form b) Hence solve algebraically Hint Maths4Scotland Higher Expand kcos(x - a): Equate coefficients: Square and add a is in 1st quadrant (sin and cos are both + ) Dividing: Put together: Solve equation. Cosine +, so 1st & 4th quadrants Previous Next Quit Quit
Hint Maths4Scotland Higher Solve the simultaneous equations where k > 0 and 0 x 360 Use tan A = sin A / cos A Divide Find acute angle Sine and cosine are both + in original equations Determine quadrant(s) Solution must be in 1st quadrant State solution Previous Next Quit Quit
Hint Maths4Scotland Higher Solve the equation in the interval 0 x 360. Use Rcos(x - a): Equate coefficients: Square and add a is in 2nd quadrant (sin + and cos - ) Dividing: Put together: Solve equation. Cosine +, so 1st & 4th quadrants Previous Next Quit Quit
Maths4Scotland Higher Table of exact values Return
Higher Circle Unit 2 Outcome 4 Intersection of a Line and a circle Thursday, 02 October 2014