(7+2i)(7-2i) решите плиз

Question

(7+2i)(7-2i) решите плиз

Answer 1

(7+2i)(7-2i)=49-4i^2

Answer 2

(7+2i)(7-2i)=0
49-4i^2=0 
 

D=0^2-4*(-4)*49=-(-16*49)=-(-784)=784

i1=28/(2*(-4))=-28/8=-3.5
i2=-28/(2*(-4))=-(-28/8)=3.5