graphing (1 Viewer)

[bboyelement]

i always get it wrong and dont really understand how to graph abs[y] = f(x)
and how is it different to y = abs[f(x)] thanks

abs = absolute

 

[zeek]

All it means is that when you put in a negative or positive value into your function, you will only be returned with a positive value.

y=|x| means that you can put negative or positive x values but the graph will always be above the x axis because only positive y values are given
x=|y| means that you can put negative or positive y values but the graph will always be to the right of the y axis because only positive x values are given

 

[bboyelement]

well abs[y] means that all the values you put into ur function will be positive but ur function may return negative values aswell i.e. you only use positive x values but can get negative or positive y values (to the right of the y-axis)
abs[f(x)] means that you can put in any value into your function and you will only get a positive output i.e. you can put negative/positive x values but ur graph will only have positive y values (above the x-axis).

uhm... so your saying only postive values ie. abs[x] can be put into the function but it may return negative values ... ???? so when do we take the negative and when do we take the positive
i actually asked my teacher and he mumbled on for ages because he couldnt explain it. this is what i told him ... abs[y] = f(x) means y = f(x) and y = -f(x) drawn together. - but apparently this is wrong

 

[zeek]

sry i messed up the explanation
i'll post up some examples for you.

EDIT: attachment added

for |y|=f(x) you have to draw f(x)=-y and f(x)=y. This will only work if they intersect the axis at the same point.

 

[bboyelement]

ohh ok so y = abs[f(x)] reflects off the x axis and abs[y] = f(x) reflects off the y axis

 

[zeek]

yup