A Level Maths Notes: C3 – Trigonometric Equations with Reciprocal Functions
The reciprocal trigonometric
functions are
and
Given
an equation of this sort we find the value of
or
first,
then find the reciprocal of this to find the value of
or
then
solve this or these equation using the normal method for finding
multiple angles of trigonometric formulae.
Example: Solve the
formula
finding
all solutions 0-360 degrees.
The expression factorises
into![]()
We follow the normal rule for quadratics by setting each factor equal to 0 and solving.
and![]()
![]()
There are no other solutions in the range 0 – 360 degrees.
Example: Solve the
formula
finding
all solutions 0-360 degrees.
The expression factorises
into![]()
We follow the normal rule for quadratics by setting each factor equal to 0 and solving.
and
and![]()
and![]()
Example: Solve the
equation
in
the range 0 – 360 degrees.
or![]()
or![]()
or
or![]()