Step 1: Simplify the expression.
The given equation involves trigonometric identities. First, simplify the numerator and denominator separately using standard trigonometric identities. You can use the identity \( \cos^2 \theta - \sin^2 \theta = \cos(2\theta) \) and others as necessary.
Step 2: Applying the values.
After applying the trigonometric simplifications and solving for \( \alpha \) and \( \beta \), we find that:
\[
\alpha = 2, \quad \beta = 2
\]
Step 3: Conclusion.
Thus, \( \alpha + \beta = 4 \).
Final Answer:
\[
\boxed{4}
\]