Plotting a polynomial that has fractions

Question

Tareq 2012-8-7

Please help me plotting this polynomial. how much should the range be , it seems matlab is not able to solve it

here is the function: = (1 / x ) [2.125 x^4 – 5.25 x ^ 3 + 12.5 x ^ 2 + 200 x + 100]

Answer 1

Sean 2012-8-7

编辑：Sean 2012-8-7

This question doesn't clearly define your problem, so I or others will have a hard time answering you definitively.

If you are trying to plot an equation, you need to define for yourself what the plotted region of interest should be. This is independent of whatever medium you use (whether software or just pen and paper).
The equation you show doesn't follow matlab syntax. If I assume that you are multiplying (1/x) by the bracketed term, you should specify it as something like:

x=-100:0.1:100; %Defining the interval of interest
y=(2.125*x.^4-5.25*x.^3+12.5*x.^2+200*x+100)./x;
plot(x,y)