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Introduction into trigonometry. Hipparchus Compiled a trigonometric table for solving triangles. Today we have all the values saved on computers : The calculator!. Born: 190 BC in Nicaea, Bithynia (now Turkey) Died: 120 BC in probably Rhodes, Greece. Hipparchus of Rhodes. Example
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Introduction into trigonometry Hipparchus Compiled a trigonometric table for solving triangles. Today we have all the values saved on computers : The calculator! Born: 190 BC in Nicaea, Bithynia (now Turkey)Died: 120 BC in probably Rhodes, Greece Hipparchus of Rhodes
Example Work out the lettered lengths for each of the following right angled triangles, giving your answers to 1 decimal place: (i) 14 cm 25° k
(ii) 21 cm a 47°
(iii) 63° b 18cm
(iv) 21 cm 75° t
(v) 9° c 5 m
Example Given triangle ABC below work out the length of BC, giving your answer to 3 significant figures. C 59° A B 78 mm
Example A piece of gutter pipe is 350cm long is angled at 6° to the horizontal. How much higher is the upper end of the guttering than its lower end?
Example When a set of ladders of length 13m are placed against a vertical wall they make an angle of 68° with the horizontal. How far up the wall does the ladder reach?
Example For the isosceles triangle below, find the length of the third side, giving your answer correct to 2 decimal places. 10cm 10cm 70° 70°