MATLAB: Find zeros in interval

Question

I try to find a solution for

Try 1

syms x t
  f=@(x)int(exp(-(t./x).^2),t,-1,1)-1.5;
  fzero(f,[0.5,2])

Try 2

solve(int(exp(-(t./x).^2),t,-1,1)==1.5,x)

The first try does not work, the second work but I can enter an inverval How can I solve an equation given an interval?

Answer 1

f=@(x)integral(@(t)exp(-(t/x).^2),-1,1)-1.5;
sol=fzero(f,[0.5,2])