Question: how to cunningly use "is" to prove equality

I have two symbolic expressions which I think may be equal, one simpler than the other. I'm trying to use "is" to ascertain the equality. I tried things like:

is(expr1=expr2) assuming beta>0 and r>0 and d>0;

which returns false,

but this is what the difference between the two expressions looks like for constellations of parameters:

[okay, so here should appear the graph, but where do I store images and other files in the new mapleprimes? impossible to find a link to "my files" or something like that, strange, oh well to be worked out later, the graph can be produced with the code below]

In other words, I suspect that expr1=expr2, at least under some assumption on no-division-by-zero, but I couldn't work out the way to show it. Any help will be much appreciated.

> restart:
  alias(gamma=gg): #the symbol gamma is reserved
  Digits:=20: interface(displayprecision=4):
> with(plots): plotsetup(default):
> params := [
    alpha = 0.5, 
    beta = 0.5, 
    sigma = 2,
    epsilon = 1/2, 
    A = 1, 
    B = 1, 
    r = 5e-2, 
    d = 5e-2
  ];
> expr1 := beta*(beta*((-(-1+beta)*(k^(-1/sigma)*(alpha*k^((sigma-1)/sigma)+1-alpha)^(1/(sigma-1))*alpha*A*(-(r+d)*(alpha*k^((sigma-1)/sigma)+1-alpha)^(-1/(sigma-1))/A/alpha*k^(1/sigma)/(-1+beta))^epsilon-r-d)/beta/(r+d))^(epsilon/(epsilon-1)))^((epsilon-1)/epsilon)+1-beta)^(1/(epsilon-1))*((-(-1+beta)*(k^(-1/sigma)*(alpha*k^((sigma-1)/sigma)+1-alpha)^(1/(sigma-1))*alpha*A*(-(r+d)*(alpha*k^((sigma-1)/sigma)+1-alpha)^(-1/(sigma-1))/A/alpha*k^(1/sigma)/(-1+beta))^epsilon-r-d)/beta/(r+d))^(epsilon/(epsilon-1)))^(-1/epsilon);
> expr2 := beta^(epsilon/(epsilon-1))*( 1-(1-beta)*((r+d)/(alpha*(1-beta)*A))^(1-epsilon)*( alpha + (1-alpha)*k^((1-sigma)/sigma) )^((epsilon-1)/(sigma-1)) )^(-1/(epsilon-1));
> plot(eval(expr1,params)-eval(expr2,params), k=0..10);
> is(expr1=expr2);
> is(expr1=expr2) assuming beta>0 and r>0 and d>0;
> is(eval(expr1,params)=eval(expr2,params));
> is(convert(eval(expr1,params),rational)=convert(eval(expr2,params),rational));