Final answer:
The student's question pertains to a trigonometric function where the cosine of x is cubed and multiplied by -2.
Step-by-step explanation:
The student has asked for the expression for the function f(x), which is given as f(x) = -2 \( \cos^3 x \). To clarify, this is a trigonometric function where the cosine of x is raised to the power of three and then multiplied by -2. This function involves concepts from algebra and trigonometry, which are typically covered in high school mathematics.