Answer to Question #118527 in Algebra for Jflows

Question

If zbase1=1−2i,zbase2=−7+i. Findzbase1−zbase2
If z1=1−2i,z2=−7+i. Findz1−z2z1−z2
a.\\(8-3i\\)
b.\\(-7-2i\\)
c.\\(7+2i\\)
d.\\(8-2i\\)

Answer 1

Given

$z_1 = 1 - 2i$ and $z_2 = -7 + i$

$z_1 - z_2 = (1 - 2i) - ( -7 + i ) = 1 - 2i + 7 - i$

$= 8 - 3i$

For next part,

$z_1 - z_2z_1 - z_2 = (1 - 2i) - (-7+i)(1-2i) - (-7+i)$

$= 1 - 2i - (-7 + i + 14i - 2i^{2})+ 7 - i$

$= 8 - 3i +5 - 15i$

$13 - 18i$

where $i^{2} = -1$