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Undefined

Undefined
is a symbol that represents a quantity with no defined value.
  • If Undefined appears in an argument of a mathematical function, equation, inequality, or Boolean operator the result will be Undefined.
ConditionalExpression with False condition evaluates to Undefined:
The number of solutions depends on the value of x:
For x=1 only the first solution is defined:
Mathematical expressions containing Undefined evaluate to Undefined:
ConditionalExpression with False condition evaluates to Undefined:
In[1]:=
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Out[1]=
 
The number of solutions depends on the value of x:
In[1]:=
Click for copyable input
Out[1]=
For x=1 only the first solution is defined:
In[2]:=
Click for copyable input
Out[2]=
Mathematical expressions containing Undefined evaluate to Undefined:
In[3]:=
Click for copyable input
Out[3]=
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