Solving for an matrix containing complex numbers












1














$$Ax = 0$$



$$A x= begin{bmatrix}-6 -2i & 5\0& 0end{bmatrix} begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}0\0end{bmatrix}$$



Simple question, but how do I solve for $x_1$ and $x_2$?



One potential answer is:



$$begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}-1+2i\-2+2iend{bmatrix}$$



I'm not sure how to get a result like this with complex numbers though. Can I get a detailed explanation on how to do this?










share|cite|improve this question





























    1














    $$Ax = 0$$



    $$A x= begin{bmatrix}-6 -2i & 5\0& 0end{bmatrix} begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}0\0end{bmatrix}$$



    Simple question, but how do I solve for $x_1$ and $x_2$?



    One potential answer is:



    $$begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}-1+2i\-2+2iend{bmatrix}$$



    I'm not sure how to get a result like this with complex numbers though. Can I get a detailed explanation on how to do this?










    share|cite|improve this question



























      1












      1








      1







      $$Ax = 0$$



      $$A x= begin{bmatrix}-6 -2i & 5\0& 0end{bmatrix} begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}0\0end{bmatrix}$$



      Simple question, but how do I solve for $x_1$ and $x_2$?



      One potential answer is:



      $$begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}-1+2i\-2+2iend{bmatrix}$$



      I'm not sure how to get a result like this with complex numbers though. Can I get a detailed explanation on how to do this?










      share|cite|improve this question















      $$Ax = 0$$



      $$A x= begin{bmatrix}-6 -2i & 5\0& 0end{bmatrix} begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}0\0end{bmatrix}$$



      Simple question, but how do I solve for $x_1$ and $x_2$?



      One potential answer is:



      $$begin{bmatrix}x_1\x_2end{bmatrix} = begin{bmatrix}-1+2i\-2+2iend{bmatrix}$$



      I'm not sure how to get a result like this with complex numbers though. Can I get a detailed explanation on how to do this?







      linear-algebra complex-numbers






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      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Nov 30 '18 at 3:40









      Robert Howard

      1,9161822




      1,9161822










      asked Nov 30 '18 at 2:57









      pylabpylab

      103




      103






















          1 Answer
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          0














          Let $x_1=-6+2i$



          $$(-6-2i)(-6+2i)+5x_2=0$$



          $$36-(2i)^2+5x_2=0$$



          $$40+5x_2=0$$



          $$x_2=-8$$






          share|cite|improve this answer























          • How would it be possible to get $x1$ and $x2$ in the form $a+bi$?
            – pylab
            Nov 30 '18 at 3:24










          • what do you mean? isn't $x_1=-6+2i$ and $x_2=-10 + 0i$ in that form?
            – Siong Thye Goh
            Nov 30 '18 at 3:53










          • If I substitute in the values $-6 + 2i$ and $-10$ into $x1$ and $x2$, I get the matrix $<-10, 0>$, but it should be $<0, 0>$
            – pylab
            Nov 30 '18 at 4:07












          • Hi, I made a mistake earlier.
            – Siong Thye Goh
            Nov 30 '18 at 4:24











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          0














          Let $x_1=-6+2i$



          $$(-6-2i)(-6+2i)+5x_2=0$$



          $$36-(2i)^2+5x_2=0$$



          $$40+5x_2=0$$



          $$x_2=-8$$






          share|cite|improve this answer























          • How would it be possible to get $x1$ and $x2$ in the form $a+bi$?
            – pylab
            Nov 30 '18 at 3:24










          • what do you mean? isn't $x_1=-6+2i$ and $x_2=-10 + 0i$ in that form?
            – Siong Thye Goh
            Nov 30 '18 at 3:53










          • If I substitute in the values $-6 + 2i$ and $-10$ into $x1$ and $x2$, I get the matrix $<-10, 0>$, but it should be $<0, 0>$
            – pylab
            Nov 30 '18 at 4:07












          • Hi, I made a mistake earlier.
            – Siong Thye Goh
            Nov 30 '18 at 4:24
















          0














          Let $x_1=-6+2i$



          $$(-6-2i)(-6+2i)+5x_2=0$$



          $$36-(2i)^2+5x_2=0$$



          $$40+5x_2=0$$



          $$x_2=-8$$






          share|cite|improve this answer























          • How would it be possible to get $x1$ and $x2$ in the form $a+bi$?
            – pylab
            Nov 30 '18 at 3:24










          • what do you mean? isn't $x_1=-6+2i$ and $x_2=-10 + 0i$ in that form?
            – Siong Thye Goh
            Nov 30 '18 at 3:53










          • If I substitute in the values $-6 + 2i$ and $-10$ into $x1$ and $x2$, I get the matrix $<-10, 0>$, but it should be $<0, 0>$
            – pylab
            Nov 30 '18 at 4:07












          • Hi, I made a mistake earlier.
            – Siong Thye Goh
            Nov 30 '18 at 4:24














          0












          0








          0






          Let $x_1=-6+2i$



          $$(-6-2i)(-6+2i)+5x_2=0$$



          $$36-(2i)^2+5x_2=0$$



          $$40+5x_2=0$$



          $$x_2=-8$$






          share|cite|improve this answer














          Let $x_1=-6+2i$



          $$(-6-2i)(-6+2i)+5x_2=0$$



          $$36-(2i)^2+5x_2=0$$



          $$40+5x_2=0$$



          $$x_2=-8$$







          share|cite|improve this answer














          share|cite|improve this answer



          share|cite|improve this answer








          edited Nov 30 '18 at 4:24

























          answered Nov 30 '18 at 3:02









          Siong Thye GohSiong Thye Goh

          100k1465117




          100k1465117












          • How would it be possible to get $x1$ and $x2$ in the form $a+bi$?
            – pylab
            Nov 30 '18 at 3:24










          • what do you mean? isn't $x_1=-6+2i$ and $x_2=-10 + 0i$ in that form?
            – Siong Thye Goh
            Nov 30 '18 at 3:53










          • If I substitute in the values $-6 + 2i$ and $-10$ into $x1$ and $x2$, I get the matrix $<-10, 0>$, but it should be $<0, 0>$
            – pylab
            Nov 30 '18 at 4:07












          • Hi, I made a mistake earlier.
            – Siong Thye Goh
            Nov 30 '18 at 4:24


















          • How would it be possible to get $x1$ and $x2$ in the form $a+bi$?
            – pylab
            Nov 30 '18 at 3:24










          • what do you mean? isn't $x_1=-6+2i$ and $x_2=-10 + 0i$ in that form?
            – Siong Thye Goh
            Nov 30 '18 at 3:53










          • If I substitute in the values $-6 + 2i$ and $-10$ into $x1$ and $x2$, I get the matrix $<-10, 0>$, but it should be $<0, 0>$
            – pylab
            Nov 30 '18 at 4:07












          • Hi, I made a mistake earlier.
            – Siong Thye Goh
            Nov 30 '18 at 4:24
















          How would it be possible to get $x1$ and $x2$ in the form $a+bi$?
          – pylab
          Nov 30 '18 at 3:24




          How would it be possible to get $x1$ and $x2$ in the form $a+bi$?
          – pylab
          Nov 30 '18 at 3:24












          what do you mean? isn't $x_1=-6+2i$ and $x_2=-10 + 0i$ in that form?
          – Siong Thye Goh
          Nov 30 '18 at 3:53




          what do you mean? isn't $x_1=-6+2i$ and $x_2=-10 + 0i$ in that form?
          – Siong Thye Goh
          Nov 30 '18 at 3:53












          If I substitute in the values $-6 + 2i$ and $-10$ into $x1$ and $x2$, I get the matrix $<-10, 0>$, but it should be $<0, 0>$
          – pylab
          Nov 30 '18 at 4:07






          If I substitute in the values $-6 + 2i$ and $-10$ into $x1$ and $x2$, I get the matrix $<-10, 0>$, but it should be $<0, 0>$
          – pylab
          Nov 30 '18 at 4:07














          Hi, I made a mistake earlier.
          – Siong Thye Goh
          Nov 30 '18 at 4:24




          Hi, I made a mistake earlier.
          – Siong Thye Goh
          Nov 30 '18 at 4:24


















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