Question

write (1+2i) (1+3i) (2+i) in form of a+bi​

Answer 1

Answer:

{(1+2i)(1+3i)}(2+i)

(1+3i+2i-6)(2+i)

(-5+5i)(2+i)

-10-5i+10i-5

-15+5i

Answer 2

Answer:

-5(3-i)

Step-by-step explanation:

=(1+2i)(1+3i)(2+i)

=[1(1+3i)+2i(1+3i)](2+i)

=(1+3i+2i+6i²)(2+i)

=(-5+5i)(2+i)

=-5(2+i)+5i(2+i)

=-10-5i+10i+5i²

=-15+5i

=-5(3-i)