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More Ratios….and more Latin. Given a triangle, how many different ratios can we make?. There are 2 more ratios we need to examine…. The next ratio, will be…. O. hypotenuse. opposite. “theta”. adjacent. This ratio was first studied by Hipparchus (Greek), in 140 BC.
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Given a triangle, how many different ratios can we make?... There are 2 more ratios we need to examine…
The next ratio, will be… O hypotenuse opposite “theta” adjacent
This ratio was first studied by Hipparchus (Greek), in 140 BC.
Aryabhata (Hindu) continued his work. For this ratio OPP/HYP, the word “Jya” was used
Brahmagupta, in 628, continued studying the same relationship and“Jya” became “Jiba” later, “Jiba became Jaib”whichmeans “fold” in Arabic
European Mathmeticians eventually translated “jaib” into latin: SINUS
Later compressed to the singular “SINE” by Edmund Gunter in 1624 Compressed again by calculator manufactorers into.. SIN
1 A X 12 12 X SIN32O = 12 FIND A: 1 12 X SIN32O = A A = 6.4 m 12 m A 32O
Given a right triangle, the 2 remaining angles must total 90O. A = 10O, then B = 80O A = 30O, then B = 60O A A “compliments” B C B
The last ratio will be… The adjacent/hyp ratio compliments the opposite/hyp ratio (called SIN)….therefore O hypotenuse opposite “theta” adjacent
Therefore, ADJ/HYP is called “Complimentary Sinus” COSINE COS
The 3 Primary Trig Ratios SINO = opp O hyp COSO = adj hyp hyp opp TANO = opp adj adj
soh cah toa 1 A X 17 FIND A: 17 X COS25O = 17 1 A = 17 X cos25O 17m A = 15.4 m 25O A
soh cah toa 1 A X 10 FIND A: 10 X SIN37O = 10 1 A = 10 X SIN37O 10 m A = 6.02 m A 37O
soh cah toa 1 A X 10 FIND A: 10 X TAN63O = 10 1 A = 10 X TAN63O 63O A = 19.6 m 10 m A
O O O O Now we have 3 working ratios for every possible right sided triangle at our fingertips….