Solve #cos^4(a)-sin^2(a)=1# ?
2 Answers
Explanation:
Given:
Substitute
Rearrange into standard quadratic form:
Factor:
There are two roots
We must discard
Use the square root on
Separate into two roots:
Use the inverse cosine function on both sides:
The above simplifies to integer multiples of
See below.
Explanation:
Here