Question

Reviewing and in need of a refreshment.

Answer 1

(4+2i)(3-5i)

Answer 2

@jim_thompson5910

Answer 3

use the FOIL rule here as well

Answer 4

and keep in mind that i^2 = -1

Answer 5

yeah, i know,. but i forget what i stands for .. i know how to simplify this question. Just a tangent off of this.

Answer 6

i is the imaginary number

\[\large i = \sqrt{-1}\]

Answer 7

squaring both sides gives you

\[\large i^2 = -1\]

Answer 8

so would the answer be 2?

Answer 9

no

Answer 10

so 12- 10^2

Answer 11

not sure how you got that

Answer 12

oh you did 4*3 = 12

and 2i*(-5i) = -10i^2

right?

Answer 13

yeah

Answer 14

well -10i^2 = -10(-1)

since i^2 = -1

Answer 15

yeah.

Answer 16

so

-10i^2 = -10(-1) = 10

which means

-10i^2 = 10

Answer 17

but that's only part of the story

Answer 18

you forgot about the other parts of the FOIL method

Answer 19

i thought you multiply 4 and 3