Answer
(a) Three roots: $x=0,\ x=1.161,\ \ x=1.509~(largest)$
(b) One root: $x=0$
Work Step by Step
(a) We are given $$f(x)=1.8 x^{4}-x^{5}-x$$
We plot the function below and estimate the roots as:
$$x=0,\ x=1.161,\ \ x=1.509$$
Thus we have three roots and $x=1.509$ is the largest.
(b) We are given $$g(x)=1.7 x^{4}-x^{5}-x$$
We plot the function below and estimate the roots as:
$$x=0 $$
Thus we have one root and $x=0$ is the largest.
