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Results tagged with assumptions
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user 19960
Questions about the function Assuming[], the $Assumptions system variable, and the Assumptions option of functions such as Simplify[] and Integrate[].
3
votes
Accepted
How do I declare that a variable represents a real number?
1. See the function ComplexExpand
ComplexExpand[Re[x + I y]]
gives
x
2. Also you can try Refine combined with Element:
Refine[Re[x + I y], Element[x, Reals]]
(*x - Im[y]*)
- 7,625
40
votes
How to tell Mathematica that certain variables are real/imaginary, integer-valued, etc
You can also use Refine with Element :
Refine[Sqrt[2] Conjugate[Sqrt[1/L]] Sin[(Pi* Conjugate[n x])/Conjugate[L]],
{Element[L, Reals], Element[n, Integers]}]
gives
and if you add that L>0:
Ref …
- 7,625