I'm not sure how to do question 4

Write a script file to plot the function f(x) = x^3 - 2x^2 - 10sin^2(x) - e^0.9x and its derivative f'(x) = 3x^2 - 4x - 20 sin(x) cos(x) - 0.9e^0.9x for -2 lessthanorequalto x lessthanorequalto 4 in ONE PLOT Plot f(x) with a solid red line and fix) with a dashed blue line; include a legend. The pressure p, volume V, and temperature T of an ideal gas are related by the following equation: p middot V = n middot R middot T, where n is the number of moles and R = 8.3145 J/(K mol) is the ideal gas constant. Plot pressure over volume (called an isotherm) for 1 mole of an ideal gas at temperatures of T = 100.200.300, and 400K for volumes ranging from 1 to 10^3 four curves/graphs in ONE PLOT using the hold command)