Question

Write this complex number in standard form?
8(cos330 degrees + i sin330 degrees)

Answer 1

8(√3/2) -1/2i) right ?

Answer 2

and how do i keep going from there?

Answer 3

just multiply by 8?

Answer 4

aah i did it wrong

Answer 5

ssooorry for some reason i was thinking 330 was 360 -60

that was stupid

Answer 6

haha, it's ok ^^

Answer 7

yes you are right

Answer 8

i don't know how to multiply that -.-

Answer 9

dont worry, we dont have to do anything complicated:

8(a+bi) = 8a + 8bi

Answer 10

here is a good link on complex numbers
http://www.clarku.edu/~djoyce/complex/polar.html

Answer 11

i mean when i plug it in i got decimal and i dont know how to turn decimal into squareroot like that?

Answer 12

its sometimes useful to think of complex numbers as vectors, if we multiply a vector by a constant, it just gets that much longer

Answer 13

oh

Answer 14

there are some trig values that are useful to know, im not sure whether you have done it yet but check this out:
we can use a couple of special right angled triangles to get sin and cos and tan of 45, 60 , 30