5-8 Graphing absolute value functions. 36. Y = |x| + 2 37. Y= |x| -7 38. Y = |x + 3| 39. Y = |x – 5| Write an equation for each translation of y = |x| 40. 5.5 units down. 41. 11 units left 42. 13 units up 43. 6.5 units right 44. Write an equation for the absolute value function at the right. PLEASE HELP.
Rules of \(\large\color{black}{ \rm shifts }\) from \(\large\color{black}{ \rm f(x) }\) to \(\large\color{black}{ \rm g(x) }\). \(\large\color{black}{ \rm f(x)=a\left| x \right| ~~~~~~~~~\rm{\Longrightarrow}~~~~~~~~\rm g(x)=a\left| x \color{blue}{ -~\rm{c} }\right| }\) \(\large\color{blue}{ ~\rm {c} }\) units to the \(\normalsize\color{blue}{ \rm right }\). \(\large\color{black}{ \rm f(x)=a\left| x \right| ~~~~~~~~~\rm{\Longrightarrow}~~~~~~~~\rm g(x)=a\left| x \color{blue}{ +~\rm{c} }\right| }\) \(\large\color{blue}{ ~\rm {c} }\) units to the \(\normalsize\color{blue}{ \rm left }\). \(\large\color{black}{ \rm f(x)=a\left| x \right| ~~~~~~~~~\rm{\Longrightarrow}~~~~~~~~\rm g(x)=a\left| x \right| \color{blue}{ +~\rm{c} }}\) \(\large\color{blue}{ ~\rm {c} }\) units \(\normalsize\color{blue}{ \rm up }\). \(\large\color{black}{ \rm f(x)=a\left| x \right| ~~~~~~~~~\rm{\Longrightarrow}~~~~~~~~\rm g(x)=a\left| x \right| \color{blue}{ -~\rm{c} }}\) \(\large\color{blue}{ ~\rm{c} }\) units \(\normalsize\color{blue}{ \rm down }\). Also, the ` reflection across the X -axis. ` \(\large\color{red}{ \rm f(x)=\left| x \right| ~~~~~~~~~\rm{\Longrightarrow}~~~~~~~~\rm g(x)=\color{blue}{ - }\left| x \right| }\) (the \(\large\color{red}{ ~\rm{f(x)} }\) and \(\normalsize\color{red}{ \rm g(x) }\) are mirrors of each other over the \(\large\color{red}{ \rm{x-axis} }\). ) \(\LARGE\color{white}{ \rm │ }\) And lastly, \(\normalsize\color{black}{ \rm{ s~t~r~e~t~c~h~i~n~g} }\) \(\large\color{black}{ \rm f(x)=\left| x \right| ~~~~~~~~~\rm{\Longrightarrow}~~~~~~~~\rm g(x)=\color{blue}{ c }\left| x \right| }\) For any real number \(\normalsize\color{blue}{ \rm{c} }\), (provided that \(\normalsize\color{blue}{ \rm{c\neq1~~or~~0} }\) ) \(\normalsize\color{black}{ \rm{1)} }\) When \(\normalsize\color{blue}{ \rm{\left| c \right| >1} }\) the (new function) \(\normalsize\color{black}{ \rm{g(x)} }\) is streched \(\normalsize\color{blue}{ \rm{ vertically} }\). (if comparing to the initial function \(\normalsize\color{black}{ \rm{f(x)} }\). ) \(\normalsize\color{black}{ \rm{2)} }\) When \(\normalsize\color{blue}{ \rm{\left| c \right| <1} }\) the (new function) \(\normalsize\color{black}{ \rm{g(x)} }\) is streched \(\normalsize\color{blue}{ \rm{ horizontally} }\). (if comparing to the initial function \(\normalsize\color{black}{ \rm{f(x)} }\). )
do you see weird codes or normal text?
Normal text.
the codes aren't working for me for some reason, so it loks like a fine set of rules, correct?
if you have some questions still, then ask away.
Yes it does.
the codes aren't working for me for some reason, so it loks like a fine set of rules, correct?
if you have some questions still, then ask away.
Still kind of confused about this, just so new to this subject.
you can see that you are adding +2 (in the first problem) right? If you know what a graph of \(\large\color{black}{ y=\left| x \right| }\) is like, then shift it accoring to the rules I posted.
so number 1 will be -2?
no not minus 2, although you are getting the 2 correctly. going from, \(\large\color{black}{ y= \left| x \right| }\), the function, \(\large\color{black}{ y=\left| x \right| \color{blue}{+2} }\) is shifted up, correct?
I guess.
looking at the third rule, your "a" is just 1, so we can re-write it as: \(\large\color{black}{ \rm f(x)=\left| x \right| ~~~~~~~~~\rm{\Longrightarrow}~~~~~~~~\rm g(x)=\left| x \right| \color{blue}{ +~\rm{c} }}\) \(\large\color{blue}{ ~\rm {c} }\) units \(\normalsize\color{blue}{ \rm up }\). you see that your "+2", is the "+c" here?
Yes I see that.
would my answer be g (x) = x + 2
you mean, \(\large\color{black}{ y= \left| x \right| +2 }\) ? and don't you have to graph it though? are you allowed to use a graphing calculator or not?
Yes I am, and yeah i mean that just didn't punch the letters in. and i'm not really sure, its a chapter review on an online school..
okay, lets start from graphing the parent function, \(\large\color{black}{ y= \left| x \right| }\), do you know how to do this, or want me to help you doing this?
Need help. I mostly learn from a teacher, kinda hard with online school not having that extra help. please
okay, lets plug in some values. you will need to tell me the following: \(\large\color{black}{ \bullet }\) \(\large\color{black}{ \left| ~-1 ~\right| =? }\) \(\large\color{black}{ \bullet }\) \(\large\color{black}{ \left| ~1 ~\right| =? }\) \(\large\color{black}{ \bullet }\) \(\large\color{black}{ \left| ~-2 ~\right| =? }\) \(\large\color{black}{ \bullet }\) \(\large\color{black}{ \left| ~2 ~\right| =? }\) tell me all of the four, what they are equal to, receptively please.
you know what \(\large\color{black}{ \left| ~-1 ~\right| }\) is equal to, right?
Is it -1?
no, the absolute value is always positive. because absolute value is basically the distance. the distance from 0 to -1, is the same as the distance from 0 to 1. Correct? So \(\large\color{black}{ \left| ~-1 ~\right| =1 }\) (just like for any positive number \(\large\color{black}{ c }\), \(\large\color{black}{ \left| ~-c~\right| =c }\) )
So you can say that: \(\large\color{black}{ \left| ~\pm1 ~\right| =1 }\) (saying that \(\large\color{black}{ \left| ~-1 ~\right| }\) and \(\large\color{black}{ \left| 1 ~\right| }\) are both equal to \(\large\color{black}{ 1 }\) )
Oh okay! so 1=1,- 2=2?
Yeah
so can you tell me what \(\large\color{black}{ \left| ~-3 ~\right| }\) will be?
3.
Yes that is correct
So we can say the following statements: (I'll use a blue color) \(\large\color{blue}{ \left| ~\pm1 ~\right| =1 }\) \(\large\color{blue}{ \left| ~\pm2 ~\right| =2 }\) \(\large\color{blue}{ \left| ~\pm3~\right| =3 }\) \(\large\color{blue}{ \left| ~\pm4 ~\right| =4 }\) yes?
and on...
Yep.
so when we have: \(\large\color{blue}{ y=\left| x~\right| }\) let's plug in values: when \(\large\color{blue}{ x=-1 }\), then \(\large\color{blue}{ y=1 }\). when \(\large\color{blue}{ x=1 }\), then \(\large\color{blue}{ y=1 }\). when \(\large\color{blue}{ x=-2 }\), then \(\large\color{blue}{ y=2 }\). when \(\large\color{blue}{ x=2 }\), then \(\large\color{blue}{ y=2 }\).
so for number one would it be x=5.5 y = 5.5?
I mean number 40- oops
no, for your problem 36 the graph is shifted from the parent function, so let first graph the parent, and then see what happens when we shift it.
Okay.
|dw:1418938917989:dw|
https://www.desmos.com/calculator/xy3lqozckt this si the graph of the parent function, \(\large\color{blue}{ y=\left| x \right| }\)
|dw:1418939054181:dw| is this right?
Join our real-time social learning platform and learn together with your friends!