What is the product of z1 and its conjugate?
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From the plot, we see that [tex]z_1=-4-3i[/tex]. Its conjugate would be [tex]\bar{z_1}=-4+3i[/tex], so that the product of the two is
[tex]z_1\bar{z_1}=(-4-3i)(-4+3i)=16-9i^2=16+9=25[/tex]
More generally, note that if [tex]z=x+yi[/tex], then
[tex]z\bar z=(x+yi)(x-yi)=x^2+y^2=|z|^2[/tex]
Answer:
The product of z1 and its conjugate is 25.
Step-by-step explanation:
In the given graph x-axis represents the real axis and y-axis represents the imaginary axis.
The end point of z1 are (0,0) and (-4,-3). So, the complex number z1 is defined as
[tex]z_1=x+iy=-4-3i[/tex]
The conjugate of z1 is
[tex]\overline {z_1}=x-iy=-4+3i[/tex]
The product of z1 and its conjugate is
[tex]z_1\overline {z_1}=(-4-3i)(-4+3i)[/tex]
[tex]z_1\overline {z_1}=-4(-4+3i)-3i(-4+3i)[/tex]
[tex]z_1\overline {z_1}=16-12i+12i-(3i)^2[/tex]
[tex]z_1\overline {z_1}=16-9(i)^2[/tex]
[tex]z_1\overline {z_1}=16-9(-1)[/tex] [tex][\because i^2=-1][/tex]
[tex]z_1\overline {z_1}=16+9=25[/tex]
Therefore the product of z1 and its conjugate is 25.