1 / 7

Warm up

Preliminary Activity. Notes. For Fun. Warm up. Activity. θ. USING THE COSINE RULE TO FIND A MISSING ANGLE. θ. θ. Back. Back. 1. The cosine ratio is the ratio of A adjacent B opposite C adjacent D opposite hypotenuse adjacent opposite hypotenuse

lorie
Download Presentation

Warm up

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Preliminary Activity Notes For Fun Warm up Activity θ USING THE COSINE RULE TO FIND A MISSING ANGLE θ θ

  2. Back Back 1. The cosine ratio is the ratio of AadjacentBoppositeC adjacentDopposite hypotenuse adjacent opposite hypotenuse 2. in the triangle sinθ is A12B 9 9 12 C 9 D12 15 15 3. Correct to four decimal places cos 53o 18' is A 0.5976 B 0.8018 C 0.6018 D 1.3416 4. If tanθ = 7 , then, to the nearest minute, θ = 5 A 54o27'B 54o28'C 16o22'D 16o23' 5. In the triangle, to the nearest minute, θ = A 38o29'B 38o30' C 38o3'D 51o30' 6. To one decimal place, x = A 20.5 B 19.1 C 19.2 D 15.0

  3. Back Back The cosine rule is another method used to find the sides and angles in non-right-angled triangles. The cosine rule: In any triangle ABC, with sides and angles as shown a2 = b2 + c2 - 2bccosA b2 = a2 + c2 - 2accosB c2 = a2 + b2 - 2abcosC The cosine rule is used to find ·the third side given two sides and the included angle ·an angle given three sides Rearranging a2 = b2 + c2 - 2bccosA gives cosA = b2 + c2 - a2 2bc which is a more convenient form for finding angles. Likewise, cosB = a2 + c2 - b2and cosC = a2 + b2 - c2 2ac 2ab

  4. Back Back Use the cosine rule to find θ correct to the nearest degree. cosA = b2 + c2 - a2 2bc cosθ = 10.72 + 23.82 - 27.52 2 x 10.7 x 23.8 θ = 99o (to the nearest degree)

  5. Back Back Complete exercise 5-07 Questions 1, 2, 4, 6, 8, 10, 12 41.7% 56.3% 75.7%

  6. Back Back $1 104 $1 096.50 $211.70 50.9% $17.25 8.5%

  7. Back Back

More Related