Please, for clarity, indicate exponentiation using the " ^ " symbol.
y = - 3x^5 ("Negative three times the 5th power of x")
y = 3x^8
y - -3(0.5)^x
y = -2^4
An exponential function has an exponent which is variable, where the base stays constant; the base cannot be a negative number or a zero. The third answer choice is the correct one, as we raise the constant 0.5 to the power x: