Answer:
the 4th answer option
Explanation:
f(x) = y = 15 - 2x²
the inverse function is the transformation of the original function, so that x gets calculated from y.
2x² + y = 15
2x² = 15 - y
x² = (15 - y)/2
x = sqrt((15 - y)/2)
and now we rename x to y and y to x, so that we have a normal function definition for the reverse function :
y = sqrt((15 - x)/2)