Question

Please help! Perform the indicated operation. Leave all answers in the form a + b i.
(1 - i ) (2 + 3 i )

a. -1 - 5 i
b. -1 + i
c. 5 + i
d. 5 - 5 i

Answer 1

do u know this:
(a+b)(c+d)=ac+ad+bc+bd
?

Answer 2

I'm familiar. Hmmm, so that's what I use?

Answer 3

and also the fact that i*i = -1
just try it....

Answer 4

\[\large{(1-i)(2+3i)=1(2+3i)-i(2+3i)}\]
\[\large{(1-i)(2+3i)=1(2)+1(3i)-i(2)-i(3i)}\]

this is the use of taht @IloveCharlie

Answer 5

*that

Answer 6

Hmm... :/

Answer 7

d.

Answer 8

what is i(3i) ?

Answer 9

i * 3i = 3 i ^2 = 3(-1) = -3

2+3i-2i+3
5+i

Answer 10

i(3i)=-3 @mathslover

Answer 11

9+2i?

Answer 12

:/

Answer 13

@mathslover already gave u answer,see the comments....

Answer 14

Yes but I can't match it up :/

Answer 15

he gave u answer as 5+i,which is option c
here are all steps together:
(1−i)(2+3i)
=1(2)+1(3i)−i(2)−i(3i)
=2+3i-2i+3
=5+i

Answer 16

Oh I understood I just must have missed it. Thank you for explaining the steps BOTH of you I appreciate it

Answer 17

Oh sorry yes :
i *3 i =3 i^2 = -3