Maths Test 4

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Created by: floevans1
Created on: 26-03-18 11:42

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Maths Test 4
- Trigonometry
  - Pythagoras
    - To find hypotenuse (C): a^2 + b^2 = c^2
      - e.g: A = 5 / B = 8, find C
        5^2 + 8^2 = C^2 / 25 + 64 = 89^2 / square root of 89 = 9.43 / C = 9.43 (2dp)
    - To find other side (a or b): c^2 - b^2 = a^2
      - e.g: C = 20 / B = 10, find A
        20^2 - 10^2 = a^2 / 400 - 100 = 300^2 / square root of 300 = 17.320/ A = 17.320 (3dp)
  - SOH, CAH, TOA: Find the side(s).
    - SOH: Sin = opposite/hypo-tenuse
      - e.g: angle = 40 degrees / H = 8, find O
        sin40 = O/H = x/8 (times 8) 8sin40 = x 5.142300 = x x (O) = 5.1 (1dp)
      - e.g: angle = 20 degrees / O = 12, find H
        sin20 = O/H = 12/x (times x) xsin20 = 12 (divide sin20) x= 12/sin20 x (H) = 35.085652 =35.1 (1dp)
    - CAH: Cos = adjacent/hypo-tenuse
      - e.g: angle = 38 degrees / H = 18, find A
        cos38 = A/H = x/18 (times 18) 18cos38=x x=14.184 = 14.2 (1dp)
      - e.g: angle = 40 degrees / A = 8, find H
        cos40 = A/H = 8/x (times x) xcos40 = 8 (divide cos40) x = 8/cos40 = 10.443 = 10.4 (1dp)
    - TOA: Tan = opposite/adja-cent
      - e.g: angle = 50 degrees / A = 9, find O
        tan50 = O/A = x/9 (times 9) 9tan50 = x 10.725782= x x = 10.7 (1dp)
      - e.g: angle = 30 degrees / O = 15, find A
        tan30 = O/A = 15/x (times x) xtan30 = 15 (divide tan30) x = 15/tan30 x= 25.980 =26.0 (1dp)
  - SOH, CAH, TOA: Find the angle(s)
    - TOA: tan = opposite/adja-cent
      - e.g: O = 8 / A = 5, find angle
        tanX= (8/5) (tan^-1) tan^-1(8/5) = 58.0 (1dp)
    - CAH: cos = adjacent/hypo-tenuse
      - e.g: A = 8 / H = 17
        cosX = (8/17) (cos^-1) cos^-1(8/17) = 61.9 (1dp)
    - SOH: sin = opposite/hypo-tenuse
      - e.g: O = 7 / H = 10
        sinX= (7/10) (sin^-1) sin^-1(7/10) = 44.4 (1dp)