Question

Help, not sure if my answer is correct

Answer 1

please state the problem and your answer.. I know you have it one the sheet but it's a bit hard to follow

Answer 2

have you solved sin(x)=0 and cos(x)=-1 yet? I can't tell from your paper.

Answer 3

oh no you are assuming the solution to sin(x)=0 is just 0 and cos(x)=-1 has solution -1?
no no
use unit circle to find when sin(x)=0 and cos(x)=-1

Answer 4

for sin(x)=0 I got 0, and same for cosx=-1 ... Im getting confused with the unit circle

Answer 5

let's replace x with theta for a sec while looking at the unit circle because that part itself can be confusing since we also use x for something else on the unit circle
\[\sin(\theta)=0 \text{ means find all angles } \theta \\ \text{ such that the y-coordinate value is 0 on the unit cicle } \]

Answer 6

2cos(0)+cos^2(0) = 0 ?
2cos(-1)+cos^2(-1) = 0? Im sure im doing it wrong

Answer 7

\[\cos(\theta)=-1 \text{ means find all angles } \theta \text{ such that } \\ \text{ the x-coordinate value is -1 on the unit circle } \]

Answer 8

soooo then

Answer 9

pi and 2 pi?

Answer 10

cos(theta)=-1 at theta=pi+2npi
sin(theta)=0 at theta=2pi+2npi and also the first one too but we don't need to repeat answers
so we could actually just write theta=npi

Answer 11

oh okay

Answer 12

so then when I sub it in would I get, 3 and -1 ?

Answer 13

(2pi+2npi,3) and (pi+2npi,-1) ?

Answer 14

looks good and if you want you can write that first one as (0+2npi,3)
but yeah that is fine

Answer 15

or just (2npi,3) lol

Answer 16

wait why would I do that for the first one again ?

Answer 17

well 2pi+2npi and 0+2npi would still give you all the same outputs just for different n-values