Operators > Boolean Operators > Example: Using the Element Of Operator
  
Example: Using the Element Of Operator
1. Use numeric and symbolic evaluation to test if 4i is a member of the set of complex numbers.
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2. Use numeric and symbolic evaluation to test if -3/4 is a member of the set of rational numbers.
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As expected, the numeric evaluation fails when number set ℚ is specified.
3. Use numeric and symbolic evaluation to test if 2 is a member of the set of real numbers.
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4. Use numeric and symbolic evaluation to test if 1.3 is a member of the set of integer numbers.
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5. Show that exact floating point representations of integers are treated by symbolic evaluation as rational numbers.
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◦ The numeric evaluation fails because only symbolic evaluation is allowed when set ℚ is specified.
◦ The symbolic evaluation fails because testing a floating point number for membership in ℚ is not defined.
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◦ The numeric evaluation fails because only symbolic evaluation is allowed when set ℚ is specified.
◦ The symbolic evaluation passes because when set ℚ is specified the exact floating point representation 10.0 of integer 10 is treated as a rational number and thus it passes the test for membership in ℚ.