Processing Math: Done
Lösung 3.1:3
Aus Online Mathematik Brückenkurs 2
(Unterschied zwischen Versionen)
Zeile 11: | Zeile 11: | ||
The expression has real part equal to zero when <math>6+a=0</math>, i.e. <math>a=-6</math>. | The expression has real part equal to zero when <math>6+a=0</math>, i.e. <math>a=-6</math>. | ||
- | NOTE: Think about how to solve the problem | + | NOTE: Think about how to solve the problem if a is not a real number. |
{{NAVCONTENT_STOP}} | {{NAVCONTENT_STOP}} |
Version vom 16:13, 25. Sep. 2008
In order to be able to see the expression's real and imaginary parts directly, we treat it as an ordinary quotient of two complex numbers and multiply top and bottom by the complex conjugate of the numerator:
2−3
ai+i
2−ai2=4+a26+a+(2−3a)i=6+a4+a2+4+a22−3ai
The expression has real part equal to zero when
NOTE: Think about how to solve the problem if a is not a real number.