(i)[4]
Prove that $f(-2)=0$ and then factorise $f(x)$ fully.
(ii)[3]
Given that $12 \times 27^y + 25 \times 9^y - 4 \times 3^y - 12 = 0$, state the corresponding value of $3^y$ and then determine $y$ correct to $3$ significant figures.
Mathematics 9709 · AS & A Level · Logarithmic and exponential functions
Logarithmic and exponential functions — practice question
The polynomial $f(x)$ is given by $f(x) = 12x^3 + 25x^2 - 4x - 12$.