General Solutions of Trigonometric Equations
Lesson · Beginner
Trigonometry
From the unit circle,
Also, sine has period . Therefore,
gives
where
Since
and cosine has period
Both tangent and cotangent have period
Hence
Solve
Either
so
or
so
Thus
Solve
so
How many solutions does
have for
First case:
This gives
Second case:
This gives
Therefore there are
solutions
Solve
Either
or
Hence
or
Now impose
The valid solutions are
Solve
Using
it becomes
Case 1:
Case 2:
Instead of using two families,