Trigonometry Examples

Find the Exact Value arccos(cos((4pi)/3))
Step 1
Apply the reference angle by finding the angle with equivalent trig values in the first quadrant. Make the expression negative because cosine is negative in the third quadrant.
Step 2
The exact value of is .
Step 3
The exact value of is .
Step 4
The result can be shown in multiple forms.
Exact Form:
Decimal Form: