Assume the graph of a function of the form y=asin(k(x+b)) is given below. Which of the following are possible values for a, k, and b?

Question

kj4uts · Answer

attachment

kj4uts · Answer

attachment

ganeshie8 · Answer

$a$ is the amplitude, the maximum distance the graph goes above the mid line

ganeshie8 · Answer

look at the graph and see if you can figure out the value of $a$

kj4uts · Answer

4

ganeshie8 · Answer

Yes! next identify the period

kj4uts · Answer

is that the space in between each other because i think it is 2

ganeshie8 · Answer

for identifying period, you may try this :  moving your head left to right, measure the distance between two consecutve peaks

ganeshie8 · Answer

you may also measure the distance between two consecutive bottoms

ganeshie8 · Answer

$k=2$ is right, but the period of given sine wave is $\pi$

ganeshie8 · Answer

so the answer must be between A or D

kj4uts · Answer

so how do i determine which one it is though?

ganeshie8 · Answer

look at the graph again 
compare it with standard sine function

ganeshie8 · Answer

it seems your graph has moved pi/4 to right side compared to the standard sine function, yes ?

kj4uts · Answer

yes positive pi/4

kj4uts · Answer

@ganeshie8  so would the answer be A. then?

ganeshie8 · Answer

sry yes A is right!

kj4uts · Answer

Thank you for your help and time :)

ganeshie8 · Answer

no wait

ganeshie8 · Answer

correct answer is option D

ganeshie8 · Answer

b = -pi/4

kj4uts · Answer

oh ok why is that?

ganeshie8 · Answer

remember how f(x-k) moves the graph of function f(x) to right by "k" units ?

kj4uts · Answer

oh ok I see