Question

Choose the function whose graph is given by (graph attached inside!)

A. y = cos(x + 1)

B. y = cos x + 1

C. y = cos x + 2

D. y = sin x + 2

**my answer: C

im not entirely too sure though... could it be A?

Answer 1

graph!

Answer 2

remember that wil cos....at 0...y = 1....so when shift up 2...that would go to 3..so that cannot be right "C" i mean

Answer 3

Let's test choice A

If x = 0, then

y = cos(x+1)

y = cos(0+1)

y = cos(1)

y = 0.9998476951564

Is that anywhere near the point (0,2) ?

Answer 4

ohhh okay... so no that's not close... does that mean it's not the answer then?

Answer 5

nope it's not the answer

Answer 6

the point (0, 0.9998476951564) lies on y = cos(x+1) and NOT (0,2)

Answer 7

right........look at what I said though.....with cosine......when x = 0.....y = 1

when you add 2 to a function...you shift it up 2....if it STARTS at 1...and shifted UP 2...that would go through y = 3..which it doesn't.....it goes through y = 2..........this should give you the big hint towards the answer

Answer 8

okay... so now we do answer choice B?
so y=cos x+1
so x=0
y=cos 0+1
y=cos 1

so y = 0.9998476951564 again?

so that's not the answer either?

Answer 9

Also, as johnweldon1993 is saying for choice C

If you plug in x = 0, you will get y = 3

So the point (0,3) lies on y = cos(x)+2 and NOT the point (0,2)

So that's why C is out

Answer 10

no, choice B is

y = cos(x) + 1

Answer 11

so that means that you plug in the x value, evaluate cosine of that x value, and THEN add 1

Answer 12

ohhh so that's different... i seeeee.. my bad!! so that means B is out as well right?? cuz 3 is not 2?

Answer 13

cos(0) + 1
cos at 0 is 1....
1 + 1 is 2

Answer 14

no I didn't say choice B was out or not

Answer 15

okay, im confused hahah :/ sorrryyy/... wait so @johnweldon1993 said... ohhh i see... cos 0 =1 after you plug in 0 as x... so B is the answer then???

Answer 16

right.....you evaluate the cos first....THEN add the 1 as @jim_thompson5910 has said

so you tell us...is B correct?

Answer 17

i believe so... because x=0 already... and we have found that y=2. so (0,2)! So B is right, right? :D

Answer 18

right :)

Answer 19

awesome! thanks :)

Answer 20

no problem!