1 / 15

Trigonometry

Trigonometry. Basic Calculations of Angles and Sides of Right Triangles. Part II. Use trigonometry to determine the size of an angle. Determine an unknown angle Example 1. To start, we will determine the size of an unknown angle when two sides of the right triangle are known. 5.5”. A. 12”.

dorian-yang
Download Presentation

Trigonometry

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. Trigonometry Basic Calculations of Angles and Sides of Right Triangles

  2. Part II Use trigonometry to determine the size of an angle.

  3. Determine an unknown angleExample 1 • To start, we will determine the size of an unknown angle when two sides of the right triangle are known. 5.5” A 12”

  4. Determine an unknown angleExample 1 • Let the unknown angle A be the reference angle. 5.5” A 12”

  5. Determine an unknown angleExample 1 • Now label the sides of the right triangle... opposite hypotenuse 5.5” A adjacent 12”

  6. Determine an unknown angleExample 1 • Note that we only know the lengths of the opposite and adjacent sides. opposite hypotenuse 5.5” A adjacent 12”

  7. Determine an unknown angleExample 1 • So we need to pick a trig function that has the opposite and adjacent sides in it... opposite 5.5” A adjacent 12”

  8. Determine an unknown angleExample 1 • Which trig function should you pick? You need to pick the tangent function since it is the only one that has both opposite and adjacent sides in it. 5.5” opposite A 12” adjacent

  9. Determine an unknown angleExample 1 • Now plug-in the numbers you have into the tangent function... opposite A = 24.6° Now use your calculator to solve. Type-in .458333, press the 2nd function key, then press the tan key 5.5” A adjacent 12”

  10. Determine an unknown angleExample 1 • How could you determine the size of the remaining angle? …this one must be 65.4° degrees. (Since 180° - 90° - 24.6° = 65.4°) 65.4° ..and this one was computed to be 24.6°… 5.5” This angle is 90°… 24.6° 12”

  11. 35 mm A 31.5 mm Determine an unknown angleExample 2 • Let’s try another one… • Determine the size of angle A.

  12. Determine an unknown angleExample 2 • To determine the other angle: • 180° - 90° - 25.8° = 64.2° 64.2° 35 mm 25.8° 31.5 mm

  13. 125 mm 132 mm A Determine an unknown angleExample 3 • Let’s try one more. • Determine the size of angle A.

  14. Determine an unknown angleExample 3 • The angle is computed to be 18.7°. 125 mm 18.7° 132 mm 71.3°

  15. Homeworkpg. 485 #3pg. 486 #7, 10,12,14,19,20

More Related