Lösungen/Solutions/
B1S2Ue/Ex7

L = Lektion/ Leçon   -- Sprechstunde / heures de consultation
W = Work / Arbeit / Travail
A  =Anhang/  Annexe / Appendice

vecLen[a_] := Sqrt[a . a];
look[a_] := {a, " or ",  N[a]}

Ueb/Ex 1      W

z1 = 4 + 5  I;  z2 = 2 - 7  I; {z1,  z2}

a

z1 + z2

b

3 z1  +  4 z2

c

z1 - 2 z2

d

z1 * z2

Ueb/Ex 2      W

φ  =  Pi/6

rot = Cos[φ] + I Sin[φ]

Dφ[φ_] := 
      Cos[φ] + I Sin[φ]

zA = 2 + I;  zB = 5 + 2  I;  zC = 3 + 3  I;

zA1 = rot zA // N

zB1 = rot zB // N

zC1 = rot zC // N

p[z_] := Point[{Re[z], Im[z]}];
h[z_] := {Re[z], Im[z]}

{h[zA], h[zB]}

Show[
        Graphics[
{PointSize[0.03], 
p[
              zA], p[zB], p[zC], p[zA1], p[zB1], 
            p[zC1], 
Line[{h[zA], h[zB]}], 
            Line[{h[zA], h[zC]}], 
            Line[{h[zB], h[zC]}], 
Line[{h[zA1], h[zB1]}], 
            Line[{h[zA1], h[zC1]}], 
            Line[{h[zB1], 
                h[zC1]}], 
Line[{{-1, 0}, {5, 0}}], 
            Line[{{0, -1}, {0, 5}}], 
Line[{{0, 0}, 
                h[zC]}], Line[{{0, 0}, h[zC1]}]
}], 
        AspectRatio -> 01];