Page 86 - Math SL HB Sem 1
P. 86
CIRCULAR FUNCTIONS AND TRIGONOMETRY
Example: Express (a) 40o in radians
(b) !1 radians in degrees
''
6
l,ength of an arc
In a unit circle, the length ofan arc subtended by an angle of d radians is d units.
Y
lo r)
( r1
01 x
figure 3
When enlarged by a factor of r, the arc length becomes rd units.
s: arc AB = rd
figure 4
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