Question

Radical expressions are killing me hoping someone can help me solve some problems!!
(9+4i)+(4-3i)
(4+4i)-(-8-i)

Answer 1

the top is just straight addition; get rid of the paranthesis

the bottom is trickier; you have to multiply the left side by (-1) and then add everything together

Answer 2

13 + i is the top

4+4i +8 +i = 12+5i make sense?

Answer 3

or is this a fraction thing that doesnt have the bar?

Answer 4

Ok, I got the first one but the second is what is giving me trouble!!

Answer 5

no 2 separate problems

Answer 6

radical usually means something under a square root looking sign;

rational tends to mean a glorified fraction....

Answer 7

Yeah there are problems that have the square root sign as well this part of the chapter is called complex numbers

Answer 8

:) I figured that cause of the "i". The "i" acts like any other variable; but the trick is that when we get i^2 it equals -1 is the only difference .

Answer 9

Yeah I have seen that in my reading. I wish there were some way to show the nth root of a number because I have some problems with the square root sign and I can't type them on here

Answer 10

So would the answer to the second one be -12-5i

Answer 11

I use sqrt(number) and cbrt(number)

otherwise its: 4root(number) 6root(number serves the same purpose)

Answer 12

oh ok, thanks

Answer 13

if all these equations are are two seperate entities:

then the top = 13+i

and the bottom = 12+5i

Answer 14

ok, that second one is confusing!!

Answer 15

think of the second one like this:

-(-8-i) means: -1(-8-i)

Answer 16

heres a tip: you recall that two negatives equals a positive right?

Answer 17

Yes

Answer 18

then just distribute that (-) thru the brackets to get:

--8 --i

+8 +i

whenever you see two negatives, make them a positive :)

Answer 19

ok, thanks!!

Answer 20

for example:

16 -(-4) = 16--4 = 16+4 = 20

Answer 21

Gotcha!! I think the parenthesis were what was throwing me off for some reason!

Answer 22

:)