Answer:
0 ≤ x ≤ ∞
Step-by-step explanation:
Square roots <em>always</em> need to be either equal to or greater than zero because it should be positive inside (unless we're working with imaginary numbers).
So the domain would be that x ≥ 0 (or the third choice ⇒ 0 ≤ x ≤ ∞).
I don't think you can find x in this case. Cosine can only go as low as -1 and as high as 1. Since 2.3 is more than 1, the answer does not exist
60 do the inverse by multiplying the numbers you have
