Question

True?

Answer 1

good

Answer 2

There is no solution to the equation sec x = 0

Answer 3

true or false

Answer 4

would it be false???

Answer 5

sec(x) never hits 0 so there's no solution making the original statement true

Answer 6

5?

Answer 7

5 would be the amplitude not the period

period = 2pi/b

where b is the coefficient of x (so b = pi/4)

Answer 8

8

Answer 9

well done so 8 = your sol'n

Answer 10

B

Answer 11

hm

what did you get when you tried factoring (2sin^2(x)-5sin(x)+2) ?

Answer 12

(sin(x)-2) (2sin (x)-1)

Answer 13

awesome

so setting sin(x) = 2 doesn't yield any sol'ns because sin(x) only goes from x = -1 to 1

but 2sin(x) -1 = 0 gives us sin(x) = 1/2

what two angles on the UC give us sin(x) = 1/2?

Answer 14

D

Answer 15

hm, not quite

check the UC again, what two angles give us sin(x) = 1/2?

Answer 16

C

Answer 17

so x = pi/6, 5pi/6, and pi/2 answer choice A

Answer 18

Oh :o

Answer 19

Sorry

Answer 20

yeah it's not a big deal but being able to read the UC is pretty important to know haha ^^" would recommend reviewing on your own time

Answer 21

A?

Answer 22

good

Answer 23

3

Answer 24

that's close but check the number in front of the function, it's not 3

Answer 25

2

Answer 26

good, so displacement = 2

Answer 27

C

Answer 28

"position at 0 is 5 cm" this implies it crosses the y-axis at (0,5) and not the origin so we would expect a cos function not a sin function

Answer 29

b

Answer 30

awesome

Answer 31

C

Answer 32

good

Answer 33

well

sin(x) = 0
sin(x) + 1 = 0 which means sin(x) = -1

so you just need to check the UC for values where sin(x) = 0 and where sin(x) = -1

remember that each coordinate on the UC is written cos(x), sin(x) which means you are looking for y-coordinates

Answer 34

sorry i was afk

Answer 35

5

Answer 36

5 is the amplitude

first calculate the period by taking 2pi/b

then calculate the frequency by taking 1/period

Answer 37

period is 8

Answer 38

good so 1/period = ?

Answer 39

1/8

Answer 40

good so 1/8 = your ans

Answer 41

False

Answer 42

this is one I was a little uncertain about b/c arcsin(x) and sin^1(x) are technically the same thing but arcsin(x) has a restricted domain so :S

Answer 43

I got a lot of contradictory answers on the web :S

Answer 44

I will just do false

Answer 45

sure ;_;

Answer 46

D

Answer 47

check one more time, you should get cos(theta) = sqrt(3)/2 so what angles would correspond to this value/

Answer 48

c

Answer 49

wait a min you said D the first time, yeah D is right ;;

Answer 50

f?

Answer 51

good

Answer 52

180

Answer 53

check the UC again, which angle(s) show that sin(theta)/cos(theta) = -1

(basically you want the angles where sin and cos are equal in magnitude but have opposite signs)

then since the range is -pi/2 to pi/2 you need to pick the angle that falls within these two values

Answer 54

1

Answer 55

now, we have to choose between 3pi/4 and 7pi/4 and neither of these are between -pi/2 and pi/2 but we can subtract 2pi from 7pi/4 to get -pi/4 = your answer

Answer 56

-pi/4?

Answer 57

yes

Answer 58

d

Answer 59

check the graph of arccos again

Answer 60

A

Answer 61

so 1 sol'n

Answer 62

B

Answer 63

@Vocaloid