A Level Maths Notes:C4 - Trigonometry
Our task is to simplify expressions of the form
by
expressing them in the form
or
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To express in terms of the first, we write,
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Remembering now that
are
all constants, we can equate the coefficients of
and
on
both sides, to give simultaneous equations:
For
(1) and
(2)
(2)/(1) gives
and
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so
where
and
are
given as above.
A similar procedure gives,
when we want to write,
as
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Example:
Write
in the form
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and
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We may also be asked to
solve equations such as
As
above, we write
and
put this equal to 1. We solve
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