# Question:evalb and sets of eqations

## Question:evalb and sets of eqations

Maple

 > Sorozatok_q1:= proc()
 > local solved, n, l, k, s_n, eq1, eq2, `a[1]`, d, MO, ret_length:
 > solved := false:
 > randomize():
 > while ( (not solved) or hasfun([MO], RootOf) ) do
 > n   := RandomTools:-Generate(integer(range=5..20)):
 > l   := RandomTools:-Generate(integer(range=2..n)):
 > k   := RandomTools:-Generate(integer(range= 1..(l-1) )):
 > s_n := RandomTools:-Generate(integer(range=5..30)):
 > eq1 := abs( `a[1]` +(k-1)*d ) = abs( `a[1]`+(l-1)*d );
 > eq2 := n * ( `a[1]` + (`a[1]` + (n-1)*d) )/2 = s_n;
 > MO  := solve( [eq1,eq2], [`a[1]`,d], Explicit=true ):
 > if not ( MO = [] ) then
 > solved := true:
 > end if:
 > end do:
 > ret_length := 4 + nops([MO]):
 > return [ret_length, n, k, l, s_n, MO];
 > end proc:
 > Out := Sorozatok_q1();

Out := [5, 9, 3, 9, 28, [[`a[1]` = 28/9, d = 0], [`a[1]` = 140/9, d = -28/9]]]

 > Out[-1];

[[`a[1]` = 28/9, d = 0], [`a[1]` = 140/9, d = -28/9]]

 > Solseq1 := op(map(xxx -> convert(xxx,set), Out[-1]));

Solseq1 := {`a[1]` = 28/9, d = 0}, {`a[1]` = 140/9, d = -28/9}

 > # copy-paste here the value of Solseq1 from the the previous output line:
 > Solseq2 := {`a[1]` = 28/9, d = 0}, {`a[1]` = 140/9, d = -28/9};

Solseq2 := {`a[1]` = 28/9, d = 0}, {`a[1]` = 140/9, d = -28/9}

 > evalb( {Solseq1} = {Solseq2});

false

 > Solseq1[1];

{`a[1]` = 28/9, d = 0}

 > Solseq2[1];

{`a[1]` = 28/9, d = 0}

 > evalb( Solseq1[1] = Solseq2[1] );

false

 > # copy-paste here the previous 2 ( identical :) sets:
 > evalb({`a[1]` = 28/9, d = 0} = {`a[1]` = 28/9, d = 0});

true

 >

Why do we get the "false "outputs here?

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