Gr12 Mathematics: Ch 4 Sum Trigonometry
81 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the formula for the sine of a difference?

  • sin(α - β) = cos α sin β - sin α cos β
  • sin(α - β) = sin α cos β + cos α sin β
  • sin(α - β) = cos α cos β - sin α sin β
  • sin(α - β) = sin α cos β - cos α sin β (correct)
  • What is the formula for the cosine of a double angle?

  • cos(2α) = 2 sin² α + 1
  • cos(2α) = cos² α - sin² α (correct)
  • cos(2α) = 1 - 2 cos² α
  • cos(2α) = 2 cos² α - 1 (correct)
  • What is the first step in solving a trigonometric equation?

  • Determine the reference angle
  • Determine where the function is positive or negative
  • Find angles within a specified interval
  • Simplify the equation using algebraic methods and trigonometric identities (correct)
  • What is the purpose of a CAST diagram?

    <p>To determine where the function is positive or negative</p> Signup and view all the answers

    What is the formula for the sine of a sum?

    <p>sin(α + β) = sin α cos β + cos α sin β</p> Signup and view all the answers

    What is the formula for the cosine of a sum?

    <p>cos(α + β) = cos α cos β - sin α sin β</p> Signup and view all the answers

    What is the formula for the sine of a double angle?

    <p>sin(2α) = 2 sin α cos α</p> Signup and view all the answers

    What is the purpose of using a reference angle?

    <p>To find the restricted values</p> Signup and view all the answers

    What is the formula for the cosine of a difference?

    <p>cos(α - β) = cos α cos β - sin α sin β</p> Signup and view all the answers

    What is the general solution to a trigonometric equation?

    <p>An infinite number of angles that satisfy the equation</p> Signup and view all the answers

    What is the formula for the cosine of a difference?

    <p>$\cos(\alpha - \beta) = \cos \alpha \cos \beta + \sin \alpha \sin \beta$</p> Signup and view all the answers

    Which method is used to derive the formula for $\cos(\alpha + \beta)$?

    <p>Using the negative angle identity</p> Signup and view all the answers

    What is the formula for the sine of a sum?

    <p>$\sin(\alpha + \beta) = \sin \alpha \cos \beta + \cos \alpha \sin \beta$</p> Signup and view all the answers

    What is the purpose of using the distance formula and cosine rule in deriving the formula for $\cos(\alpha - \beta)$?

    <p>To equate two expressions for KL^2</p> Signup and view all the answers

    What is the formula for the cosine of a sum?

    <p>$\cos(\alpha + \beta) = \cos \alpha \cos \beta - \sin \alpha \sin \beta$</p> Signup and view all the answers

    What is the formula for the sine of a difference?

    <p>$\sin(\alpha - \beta) = \sin \alpha \cos \beta - \cos \alpha \sin \beta$</p> Signup and view all the answers

    Why are the even-odd identities used in deriving the formula for $\cos(\alpha + \beta)$?

    <p>To simplify the expression for $\cos(-\beta)$</p> Signup and view all the answers

    What is the purpose of deriving the compound angle formulas?

    <p>To express trigonometric functions of a sum or difference in terms of functions of the individual angles</p> Signup and view all the answers

    What is the formula to find the general solution for sin theta = x?

    <p>theta = 180^degree - sin^(-1)x + k * 360^degree</p> Signup and view all the answers

    What is the formula for the area of a triangle using the area rule?

    <p>All of the above</p> Signup and view all the answers

    When should you use the cosine rule?

    <p>When no right angle is given, and either two sides and the included angle or three sides are given</p> Signup and view all the answers

    What is the formula for the height of a pole using the sine and tangent rules?

    <p>h = (d sin alpha)/(sin beta) tan beta</p> Signup and view all the answers

    What is the formula for the height of a building using the sine rule?

    <p>h = (b sin alpha sin theta)/(sin(beta + theta))</p> Signup and view all the answers

    What is the formula for tan theta = x?

    <p>theta = tan^(-1)x + k * 180^degree</p> Signup and view all the answers

    When should you use the sine rule?

    <p>When no right angle is given, and two sides and an angle (not the included angle) are given</p> Signup and view all the answers

    What is the formula for the area of a triangle using the sine rule?

    <p>Area = (1/2)ab sin C</p> Signup and view all the answers

    What is the formula for cos theta = x?

    <p>theta = cos^(-1)x + k * 360^degree</p> Signup and view all the answers

    What is the formula for $\cos(\alpha - eta)$?

    <p>$\cos \alpha \cos eta + \sin \alpha \sin eta$</p> Signup and view all the answers

    What is the formula for $\sin(\alpha + eta)$?

    <p>$\sin \alpha \cos eta + \cos \alpha \sin eta$</p> Signup and view all the answers

    Which method is used to derive the formula for $\cos(\alpha - eta)$?

    <p>Using the distance formula and cosine rule</p> Signup and view all the answers

    What is the purpose of using the distance formula and cosine rule in deriving the formula for $\cos(\alpha - eta)$?

    <p>To derive the formula for $\cos(\alpha - eta)$</p> Signup and view all the answers

    Why are the even-odd identities used in deriving the formula for $\cos(\alpha + eta)$?

    <p>To rewrite the angle as a difference</p> Signup and view all the answers

    What is the formula for $\sin(\alpha - eta)$?

    <p>$\sin \alpha \cos eta - \cos \alpha \sin eta$</p> Signup and view all the answers

    What is the purpose of deriving the compound angle formulas?

    <p>To extend trigonometric identities</p> Signup and view all the answers

    Which formula is used as a stepping stone to derive the formula for $\cos(\alpha + eta)$?

    <p>$\cos(\alpha - eta) = \cos \alpha \cos eta + \sin \alpha \sin eta$</p> Signup and view all the answers

    What is the formula for cos(α - β)?

    <p>cos(α)cos(β) - sin(α)sin(β)</p> Signup and view all the answers

    If sin(α) = 2/3 and cos(α) = sqrt(5)/3, then what is the value of cos(2α)?

    <p>-1/9</p> Signup and view all the answers

    What is the formula for sin(α + β)?

    <p>sin(α)cos(β) + cos(α)sin(β)</p> Signup and view all the answers

    What is the purpose of using a CAST diagram in solving trigonometric equations?

    <p>To determine where the function is positive or negative</p> Signup and view all the answers

    If cos(α) = 1/2, then what is the value of cos(2α)?

    <p>3/4</p> Signup and view all the answers

    What is the formula for cos(α + β)?

    <p>cos(α)cos(β) - sin(α)sin(β)</p> Signup and view all the answers

    If sin(α) = 1/2 and cos(α) = sqrt(3)/2, then what is the value of sin(2α)?

    <p>sqrt(3)/2</p> Signup and view all the answers

    What is the first step in solving a trigonometric equation?

    <p>Simplify the equation using algebraic methods</p> Signup and view all the answers

    If sin(α) = 3/5 and cos(α) = 4/5, then what is the value of cos(2α)?

    <p>-7/25</p> Signup and view all the answers

    What is the general solution for the equation tan θ = x?

    <p>θ = tan⁻¹x + k ⋅ 180°, where k is an integer</p> Signup and view all the answers

    What is the formula for the area of a triangle with sides a, b, and angle C?

    <p>All of the above</p> Signup and view all the answers

    When should you use the sine rule?

    <p>When no right angle is given, and either two sides and an angle or two angles and a side are given</p> Signup and view all the answers

    What is the formula for the height of a building using the sine rule?

    <p>h = (b sin α sin θ) / (sin(β + θ))</p> Signup and view all the answers

    What is the formula for the area of a triangle with sides a and b, and angle C?

    <p>Area = (1/2)ab sin C</p> Signup and view all the answers

    When should you use the cosine rule?

    <p>When no right angle is given, and three sides are given</p> Signup and view all the answers

    What is the formula for the height of a pole using the sine and tangent rules?

    <p>h = (d sin α) / (sin β) tan β</p> Signup and view all the answers

    What is the general solution for the equation sin θ = x?

    <p>θ = sin⁻¹x + k ⋅ 180° or θ = 180° - sin⁻¹x + k ⋅ 360°</p> Signup and view all the answers

    What is the formula for the area of a triangle with sides a, b, and c?

    <p>Area = (1/2)ab sin C</p> Signup and view all the answers

    What is the general approach to solving three-dimensional problems?

    <p>Draw a sketch, consider the given information, apply appropriate rules, and calculate the desired quantities</p> Signup and view all the answers

    What is the sine of a 30° angle minus a 45° angle?

    <p>√2/2 - 1/2</p> Signup and view all the answers

    If sin(α) = 2/3 and cos(α) = √5/3, what is the value of sin(2α)?

    <p>8√5/9</p> Signup and view all the answers

    What is the cosine of a 30° angle plus a 45° angle?

    <p>√2/2 + 1/2</p> Signup and view all the answers

    If cos(α) = 1/2 and sin(α) = √3/2, what is the value of cos(2α)?

    <p>3/4</p> Signup and view all the answers

    What is the sine of a 60° angle plus a 30° angle?

    <p>√3/2</p> Signup and view all the answers

    What is the cosine of a 45° angle minus a 30° angle?

    <p>√2/2 - 1/2</p> Signup and view all the answers

    If (\cos(\alpha - \beta) = \cos \alpha \cos \beta + \sin \alpha \sin \beta), then what is (\cos(\alpha + \beta))?

    <p>\cos \alpha \cos \beta - \sin \alpha \sin \beta</p> Signup and view all the answers

    If cos(α) = 3/5 and sin(α) = 4/5, what is the value of cos(2α)?

    <p>-7/25</p> Signup and view all the answers

    What is the purpose of using the distance formula and cosine rule in deriving the formula for (\cos(\alpha - \beta))?

    <p>To simplify the expression ((\cos \alpha - \cos \beta)^2 + (\sin \alpha - \sin \beta)^2)</p> Signup and view all the answers

    What is the sine of a 75° angle?

    <p>√2 - 1/2</p> Signup and view all the answers

    What is the key step in deriving the formula for (\cos(\alpha + \beta))?

    <p>Using the negative angle identity</p> Signup and view all the answers

    If (\sin \alpha = \frac{2}{3}) and (\cos \alpha = \frac{\sqrt{5}}{3}), then what is the value of (\cos(2\alpha))?

    <p>\frac{-1}{9}</p> Signup and view all the answers

    If sin(α) = 2/3 and cos(α) = √5/3, what is the value of cos(2α)?

    <p>-4/9</p> Signup and view all the answers

    What is the formula for (\sin(\alpha - \beta))?

    <p>\sin \alpha \cos \beta - \cos \alpha \sin \beta</p> Signup and view all the answers

    If (\cos(\alpha + \beta) = \cos \alpha \cos \beta - \sin \alpha \sin \beta), then what is (\cos(\alpha - \beta))?

    <p>\cos \alpha \cos \beta + \sin \alpha \sin \beta</p> Signup and view all the answers

    What is the key step in deriving the formula for (\sin(\alpha + \beta))?

    <p>Applying the sine difference formula</p> Signup and view all the answers

    What is the purpose of deriving the compound angle formulas?

    <p>To simplify trigonometric expressions</p> Signup and view all the answers

    What is the general solution to the equation sin(θ) = x in the interval [0°, 360°]?

    <p>θ = sin⁻¹(x) + k × 360°</p> Signup and view all the answers

    For the equation cos(θ) = x, what is the value of θ in the interval [0°, 360°]?

    <p>θ = cos⁻¹(x) or θ = 180° - cos⁻¹(x)</p> Signup and view all the answers

    What is the formula for the area of a triangle with sides a, b, and angle C?

    <p>Area = (1/2)ab sin(C)</p> Signup and view all the answers

    When should you use the cosine rule in solving triangular problems?

    <p>When no right angle is given, and either two sides and an angle or three sides are given.</p> Signup and view all the answers

    What is the formula for the height of a pole using the sine and tangent rules?

    <p>h = (d sin(α)) / sin(β)</p> Signup and view all the answers

    What is the formula for the area of a triangle with sides a and b, and angle C?

    <p>Area = (1/2)ab sin(C)</p> Signup and view all the answers

    When should you use the sine rule in solving triangular problems?

    <p>When no right angle is given, and either two angles and a side or two sides and an angle are given.</p> Signup and view all the answers

    What is the formula for the height of a building using the sine rule?

    <p>h = (b sin(α) sin(θ)) / sin(β + θ)</p> Signup and view all the answers

    What is the general solution to the equation tan(θ) = x in the interval [0°, 360°]?

    <p>θ = tan⁻¹(x) + k × 180°</p> Signup and view all the answers

    What is the formula for the area of a triangle with sides a, b, and c?

    <p>Area = √(s(s-a)(s-b)(s-c))</p> Signup and view all the answers

    More Like This

    Use Quizgecko on...
    Browser
    Browser