How to make plot of an equation？

I want to plot the equation with E in x-axis and n in y-axis:

And here is my code and the respond:

E = linspace(-10,10,0.1);

n = @(E, r1, h_, Vf) ((E.^2)+r1*E.)/(2*pi*h_*h_*Vf*Vf);

r1 = 0.4;

h_ = 6.62607004*10^-34;

Vf = 10^6;

plot(E,n);

File: Q5_d.m Line: 3 Column: 35

Invalid expression. When calling a function or indexing a variable, use parentheses. Otherwise, check for mismatched delimiters.

How to fix it?

Answer 1

[KSSV]

You messed up with linspace and the defined function.

E = -10:0.1:10 ; 

r1 = 0.4; 
h_ = 6.62607004*10^-34; 
Vf = 10^6; 

n = (E.^2+r1*E)./(2*pi*h_*h_*Vf*Vf);
plot(E,n);

If you want to make a function like yours:

E = linspace(-10,10,100); 
n = @(E, r1, h_, Vf) ((E.^2)+r1*E)./(2*pi*h_*h_*Vf*Vf);
r1 = 0.4; 
h_ = 6.62607004*10^-34; 
Vf = 10^6; 
plot(E,n(E,r1,h_,Vf));