Question

ZERO polynominal function of f(x) = x^3 + 4x^2 - 9x - 36

Answer 1

f(x) = x³ + 4x² - 9x - 36
f(x)=(x³+4x²)-(9x+36)=x²(x+4)-9(x+4)=(x+4)(x²-9)=(x+4)(x²-3²)=(x+4)(x-3)(x+3)=0
so x₁=-4, x₂=-3, x₃=3