A ratio compares two quantities.
penguins = 8
whales = 4
8:4 , now simplify
8/4 = 2
4/4 = 1
2:1 is the ratio.
Final answer: 2:1
From the double-angle identity,

we can rewritte our given equation as:

By factoring 2cosx on the left hand side, we have

This equation has 2 solutions when

From equation (A), we obtain

and from equation (B), we have

On the other hand, we can find one more solution from the original equation by substituting x=0, that is,

then, x=0 is another solution. In summary, we have obtained the following solutions:

However, the intersection of the last set is empty. So the unique solution is x=0 as we can corroborate on the following picture:
Therefore, the solution set is: {0}
Answer:
3
Step-by-step explanation 3