How to plot a functions in matlab

x ranges from 10-50 and y = [exp(-x)/x] - [exp(-(2+x))/(2+x)]

Answer 1

[the cyclist]

x = 10:0.1:50;
y = (exp(-x)./x) - (exp(-(2+x))./(2+x));
plot(x,y)

Answer 2

[Youssef Khmou]

1. Using function handle :

 >>f=@(x) (exp(-x)./x)-(exp(-(2+x))./(2+x))
 >>x=10:0.1:50;
 >>plot(x,f(x))

2. Alternative using again Function Handle ;

 >>f=@(x) (exp(-x)./x)-(exp(-(2+x))./(2+x))
 >>fplot(f,[10 50])

3. Using M function in M file :

 % Save the function in M file 
 function y=R(x)
 y=(exp(-x)./x)-(exp(-(2+x))./(2+x));
 %------------------------------------ 
 % In the command prompt :
 >>x=[10:0.01:50];
 >>figure, plot(x,R(x))

4. Using Symbolic variables :

 >>syms x
 >>f=(exp(-x)./x)-(exp(-(2+x))./(2+x))
 >>ezplot(f,[10 50])

Answer 3

[Fernando Fernandes]

How could I plot a function of two variables r_d and t_d? I'd like to keep r_d constant and plot t_d.. after I want to keep t_d constant and plot r_d. The function is: q(r_d, t_d)=exp((-r_d)^2/(4*t_d))