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Chapter 2 Trigonometry Part 1 of 2 Many students begin physics without having been exposed to trigonometry, or having forgotten what they once knew about it. This, however, is not cause for consternation, as the amount of trig needed for this course is easily learned. Trig is based on two Important Facts : Important Fact #1 : The Pythagorean Theorem is True! 1. Use the Pythagorean T heorem to find the missing side on each r ight triangle: a) b) c) d) a) a 2 + b 2 = c 2 (6 cm) 2 + (10 cm) 2 = c 2 c = 11.7 cm b) a 2 + b 2 = c 2 a 2 = c 2 - b 2 a 2 = (12 m) 2 - (10 m) 2 a = 6.6 m c) a 2 + b 2 = c 2 (9.4 ft) 2 + (17.1 ft) 2 = c 2 c = 19.5 ft d) a 2 + b 2 = c 2 a 2 = c 2 - b 2 a 2 = (286 in) 2 - (97 in) 2 a = 269 in Important Fact #2: Note that as a triangle grows in size, its angles remain the same and its sides retain their proportionality. That is, the ratio of any two sides will be unchanged.
