Evaluate the expression and write the result in the form
a + bi.

(9 + 3i)(3 − i) over/
3 + i

Question

Evaluate the expression and write the result in the form 
a + bi.
 
(9 + 3i)(3 − i) over/
3 + i

anonymous · Answer

$$\frac{(9+3i)(3-i)}{3+i}\times\frac{3-i}{3-i}$$

anonymous · Answer

I got that far

anonymous · Answer

whats next?

anonymous · Answer

$$\frac{(27-9i+9i-3i^2)*(3-i)}{9-i^2}$$

anonymous · Answer

$$\frac{(27-(3*-1)*(3-i)}{9-(-1)}$$

anonymous · Answer

$$\frac{(27+3)*(3-i)}{10}=\frac{90-30i}{10}$$

myininaya · Answer

oops i forgot to click post lol

myininaya · Answer

i had something different

anonymous · Answer

$$9-3i$$

myininaya · Answer

$$\frac{(9+3i)(3-i)}{3+i}=\frac{27-9i+9i-3i^2}{3+i}=\frac{27-3(-1)}{3+i}=\frac{30}{3+i}$$
$$=\frac{30}{3+i}*\frac{3-i}{3-i}=\frac{90-30i}{9-i^2}=\frac{90-30i}{9-(-1)}=\frac{90-30i}{10}$$
no you are right

anonymous · Answer

I check it correct answer http://www.mathway.com/answer.aspx?p=calg?p=((9+3i)(3-i))SMB10(3+i)?p=22?p=?p=?p=?p=?p=0?p=?p=0?p=?p=

myininaya · Answer

=9-3i

myininaya · Answer

i couldn't remember what i had before i forgot to click post lol

anonymous · Answer

ty