Function f(x)
f =exp(x)
end

Function e(x)
e =exp(x)
end

Function p3(x)
p3 =x**3+3*x*x+3*x+1
end

Function e_20(x)
e_20 =exp(-x*x)
end

Function e_2(x)
e_2 =-2*x*exp(-x*x)
end
