Final answer:
To find x in the equation 30+f(x)+x² f(x)³=0 and given that f(-1)=-3, substitute f(x) with -3, simplify the equation, and solve the resulting quadratic equation to find the values of x.
Step-by-step explanation:
To find x in the equation 30+f(x)+x² f(x)³=0 and given that f(-1)=-3, you can start by substituting f(x) with -3 since f(-1)=-3. This will give you 30 - 3 + x² (-3)³=0. Next, simplify the equation by performing the calculations. You should end up with a quadratic equation x² + 9x + 27 = 0. Finally, you can solve this quadratic equation using methods such as factoring, completing the square, or using the quadratic formula to find the values of x.