Here's my problem could someone show me what the steps are?
$$2 \cos \alpha \cos \beta = \cos( \alpha + \beta) + \cos( \alpha − \beta)$$
Here's my problem:
Here's my problem could someone show me what the steps are?
$$2 \cos \alpha \cos \beta = \cos( \alpha + \beta) + \cos( \alpha − \beta)$$
Here's my problem: