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<b>let </b><font color="Maroon">L1</font> be   <a href="lattices.html#NM1">Lattice</a>, <font color="Maroon">L2</font> be   <a href="lattices.html#NM1">Lattice</a>;<br/><b>let </b><font color="Maroon">f</font> be   <a href="funct_2.html#NM1">Function</a> of the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">L1</font>,the <a href="struct_0.html#U1">carrier</a> of <font color="Maroon">L2</font>;<br/>



<a NAME="E1:19"/><i><font color="Green">E24</font></i>: 
( <font color="Maroon">f</font> is    <a href="lattice4.html#M1">Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> implies ( <font color="Maroon">f</font> is    <a href="vectsp_8.html#M4" target="_self">sup-Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> &amp; <font color="Maroon">f</font> is    <a href="vectsp_8.html#M3" target="_self">Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> ) )
 
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="19_1"><b>proof </b></a><div class="add">

<b>assume </b><a NAME="E1:19_1"/>
<font color="Maroon">f</font> is    <a href="lattice4.html#M1">Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font>
 ;<br/>

<a NAME="E2:19_1"/><b>then </b>
for <font color="Olive">a</font>, <font color="Olive">b</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L1</font> holds <br/> ( <font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <span class="p1">(<span class="default"><font color="Olive">a</font> <a href="lattices.html#K3">"\/"</a> <font color="Olive">b</font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">a</font></span>)</span> <a href="lattices.html#K3">"\/"</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">b</font></span>)</span> &amp; <font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <span class="p1">(<span class="default"><font color="Olive">a</font> <a href="lattices.html#K4">"/\"</a> <font color="Olive">b</font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">a</font></span>)</span> <a href="lattices.html#K4">"/\"</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">b</font></span>)</span> )
 
<b>by </b><i><a class="ref" href="lattice4.html#D1">LATTICE4:def 1</a></i>;<br/>
<b>hence </b><a NAME="E3:19_1"/>
( <font color="Maroon">f</font> is    <a href="vectsp_8.html#M4" target="_self">sup-Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> &amp; <font color="Maroon">f</font> is    <a href="vectsp_8.html#M3" target="_self">Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> )
 <b>by </b><i>, </i>;<br/>


</div><b>end;</b></div>
<a NAME="E2:19"/>
( <font color="Maroon">f</font> is    <a href="vectsp_8.html#M4" target="_self">sup-Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> &amp; <font color="Maroon">f</font> is    <a href="vectsp_8.html#M3" target="_self">Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> implies <font color="Maroon">f</font> is    <a href="lattice4.html#M1">Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> )
 
<div><a class="txt" onclick="hs2(this)" href="javascript:()" title="19_2"><b>proof </b></a><div class="add">

<b>assume </b><a NAME="E1:19_2"/>
( <font color="Maroon">f</font> is    <a href="vectsp_8.html#M4" target="_self">sup-Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> &amp; <font color="Maroon">f</font> is    <a href="vectsp_8.html#M3" target="_self">Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> )
 ;<br/>

<a NAME="E2:19_2"/><b>then </b>
for <font color="Olive">a</font>, <font color="Olive">b</font> being  <a href="struct_0.html#NM1">Element</a> of <font color="Maroon">L1</font> holds <br/> ( <font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <span class="p1">(<span class="default"><font color="Olive">a</font> <a href="lattices.html#K3">"\/"</a> <font color="Olive">b</font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">a</font></span>)</span> <a href="lattices.html#K3">"\/"</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">b</font></span>)</span> &amp; <font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <span class="p1">(<span class="default"><font color="Olive">a</font> <a href="lattices.html#K4">"/\"</a> <font color="Olive">b</font></span>)</span> <a href="hidden.html#R1">=</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">a</font></span>)</span> <a href="lattices.html#K4">"/\"</a> <span class="p1">(<span class="default"><font color="Maroon">f</font> <a href="funct_2.html#K3">.</a> <font color="Olive">b</font></span>)</span> )
 
<b>by </b><i>, </i>;<br/>
<b>hence </b><a NAME="E3:19_2"/>
<font color="Maroon">f</font> is    <a href="lattice4.html#M1">Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font>
 <b>by </b><i><a class="ref" href="lattice4.html#D1">LATTICE4:def 1</a></i>;<br/>


</div><b>end;</b></div>
<b>hence </b><a NAME="E3:19"/>
( <font color="Maroon">f</font> is    <a href="lattice4.html#M1">Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> iff ( <font color="Maroon">f</font> is    <a href="vectsp_8.html#M4" target="_self">sup-Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> &amp; <font color="Maroon">f</font> is    <a href="vectsp_8.html#M3" target="_self">Semilattice-Homomorphism</a> of <font color="Maroon">L1</font>,<font color="Maroon">L2</font> ) )
 <b>by </b><i/>;<br/>


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