If or is negative,
your calculator will give
in the domain.
sin tan
0
μμ
μ
-___wp<μ<
PARAMETRIC
PLOTTER
The arrow
shows the angle that
your calculator gives.
green
-1 1 x
1 y
-1
- We
2.30
-1 1 x O
1 y
-1
-0.4
-0.412
O
-1 1 x
1 y
-1
-0.322
O
216 The unit circle and radian measure (Chapter 8)
Example 11 Self Tutor
Find two anglesμon the unit circle, with 06 μ 62 ¼, such that:
a sinμ=¡ 0 : 4 b cosμ=¡^23 c tanμ=¡^13
a sin¡^1 (¡ 0 :4)¼¡ 0 : 412
But 06 μ 62 ¼
) μ¼¼+0: 412 or
2 ¼¡ 0 : 412
) μ¼ 3 : 55 or 5 : 87
b cos¡^1 (¡^23 )¼ 2 : 30
But 06 μ 62 ¼
) μ¼ 2 : 30 or
2 ¼¡ 2 : 30
) μ¼ 2 : 30 or 3 : 98
c tan¡^1 (¡^13 )¼¡ 0 : 322
But 06 μ 62 ¼
) μ¼¼¡ 0 : 322 or
2 ¼¡ 0 : 322
) μ¼ 2 : 82 or 5 : 96
2 Find two anglesμon the unit circle, with 06 μ 62 ¼, such that:
a cosμ=¡^14 b sinμ=0 c tanμ=¡ 3 : 1
d sinμ=¡ 0 : 421 e tanμ=¡ 6 : 67 f cosμ=¡ 172
g tanμ=¡
p
5 h cosμ=¡p^13 i sinμ=¡
p 2
p
5
Discovery 2 Parametric equations
#endboxedheading
Usually we write functions in the form y=f(x).
For example: y=3x+7, y=x^2 ¡ 6 x+8, y= sinx
However, sometimes it is useful to expressbothxandyin terms
of another variablet, called theparameter. In this case we say
we haveparametric equations.
What to do:
1aUse the graphing package to plot
f(x,y):x= cost, y= sint, 0 ± 6 t 6360 ±g.
Use the same scale on both axes.
The use of parametric
equations is not required
for the syllabus.
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100 100 4037 Cambridge
Additional Mathematics
Y:\HAESE\CAM4037\CamAdd_08\216CamAdd_08.cdr Friday, 4 April 2014 12:57:02 PM BRIAN