z1+z2=-3-4i+(1-3i)=-2-7i z1*z2=(-3-4i)*(1-3i)=-3*1-4i*1+9i+12(i^2)=-3+5i-12=5i-15 z1/z2=(-3-4i)/(1-3i)=(-3-4i)*(1+3i)/((1-3i)*(1+3i)=(-3-4i-9i-12(i^2))/(1-9(i^2))=(-3-13i+12)/(1+9)=(9-13i)/10=0.9-1.3i
z1+z2=-3-4i+(1-3i)=-2-7i
z1*z2=(-3-4i)*(1-3i)=-3*1-4i*1+9i+12(i^2)=-3+5i-12=5i-15
z1/z2=(-3-4i)/(1-3i)=(-3-4i)*(1+3i)/((1-3i)*(1+3i)=(-3-4i-9i-12(i^2))/(1-9(i^2))=(-3-13i+12)/(1+9)=(9-13i)/10=0.9-1.3i