WolframAlpha computational knowledge AI
Plot[Piecewise[{{0, 0 < x <= 1000}, {1.5 * (x-1000) / 1000, 1000 < x < 5*10^6}, {(x-1000)/1000 + 2488.5, 5*10^6 < x < 20*10^6}}], {x, 0, 20*10^6}]