Find the interval on which the function $f\left(x\right)=2x^2-3x$ is strictly increasing.

Find the interval on which the function $f\left(x\right)=2x^2-3x$ is strictly decreasing.

Find the interval on which the function $f\left(x\right)=2x^3-3x^2-36x+7$ is strictly increasing.

Find the interval on which the function $f\left(x\right)=2x^3-3x^2-36x+7$ is strictly decreasing.

Find the interval on which the function $f\left(x\right)=6-9x-x^2$ is strictly increasing. 

Find the interval on which the function $f\left(x\right)=6-9x-x^2$ is strictly decreasing.

Find the intervals on which function $f\left(x\right)=\left(x^4-\frac{x^3}{3}\right)$ is increasing.

Find the interval on which function $f\left(x\right)=\left(x^4-\frac{x^3}{3}\right)$ is decreasing.

Find the interval on which the following function $f\left(x\right)=x^3-12x^2-36x+17$ is increasing.