MATLAB: How to write an exponential eqn.

i want to write this the following equation in matlab

e-((r+1)^2)/2

how should i write the exponential symbol "e"

a=100
y=exp(a)

I've got a sol. for those who are in the same situation

try using >>>subs()

for ex.

[subs(f,{x,y,z},{0,0,1}) subs(f,{x,y,z},{0,1,0}) subs(f,{x,y,z},{1,0,0})]

result is

ans = [0 3 2]

You can use fsolve() for such problems. For example

fun = @(x) exp(-0.005*x).*cos(0.05*(2000-0.01*x.^2).^(0.05))-0.01
sol = fsolve(fun, rand())

Note that, the code you included in your question contain exp(1)^(-0.005*x). That is very inefficient.

If you just want to graph it then try

x = linspace(0,2*pi,100);
y = exp(-0.005*x).*cos(0.05*(2000-0.01*x.^2).^(0.05))-0.01;
plot(x,y)

Note that I have replaced * with .* and ^ with .^. Read about element-wise operators here: https://www.mathworks.com/help/matlab/matlab_prog/array-vs-matrix-operations.html