Question #265f1
2 Answers
Explanation:
Use the double angle formula
to rewrite the equation in the form
Substituting
Since
Thus, either
Explanation:
Starting with
Add
Square both sides to obtain
Multiply both sides by 2, then put everything on one side:
You've essentially got a simple quadratic equation to factor now. If
=>
So
Like solving for the zeros in any quadratic equation, set each factor equal to zero to find the solutions:
We know from the unit circle that
The next factor:
Likewise, the unit circle shows us that
So,
Or in degrees: