Trigonometry Basics Right Triangle Trigonometry Review n The
Trigonometry Basics Right Triangle Trigonometry
Review n The sin function: sin A = hypotenuse opposite A
Review n The cosine function. cos A = hypotenuse A adjacent
Review n The tangent function. tan A = opposite A adjacent
Trig Sine. Functions Functionand the Calculator Try each of these on your calculator: n sin 55° n cos 10° n tan 87° n
Inverse Function Sine Function n Using sin-1 (inverse sin): If then n 0. 7315 = sin-1 (0. 7315) = Solve for θ if sin θ = 0. 2419 sin θ θ
Inverse Cosine Function n Using cos-1 (inverse cosine): If then n 0. 9272 = cos-1 (0. 9272) = Solve for θ if cos θ = 0. 5150 cos θ θ
Inverse Tangent Function n Using tan-1 (inverse tangent): If then n 0. 5543 = tan-1 (0. 5543) = Solve for θ if tan θ = 28. 64 tan θ θ
Review These are the only trig functions you will be using in this course. n You need to memorize each one. n Use the memory device: SOH CAH TOA n
Most Common Application: r θ x y
Review Solve for x: x = sin 30° x = cos 45° x = tan 20° n
Review n Solve for θ: 0. 7987 = sin θ 0. 9272 = cos θ 2. 145 = tan θ
What if it’s not a right triangle? n Law of Cosines - The square of the magnitude of the resultant vector is equal to the sum of the magnitude of the squares of the two vectors, minus two times the product of the magnitudes of the vectors, multiplied by the cosine of the angle between them. R 2 = A 2 + B 2 – 2 AB cosθ θ
What if it’s not a right triangle? - Use the Law of Cosines: The Law of Cosines In any triangle ABC, with sides a, b, and c,
- Slides: 15