Даны два числа z1=5+10i и z2=2-i.

Найти: z1+z2; z1-z2; z1*z2; z1:z3

1) z1+z2 = 5+10i + 2-i = 7+9i

2) z1-z2 = 5+10i - (2-i) = 5+10i - 2+i = 3+11i

3) z1*z2 = (5+10i) * (2-i) = 10-5i+20i-10i2 = 10+15i - 10i2 = 2+3i - 2i2

4) z1/z2 = (5+10i) / (2-i) = (5+10i) * 1 / (2-i) = 5/2-i + 5+10i/2-i = 5+10i / 2-i