Login

Welcome, Guest. Please login or register.

November 08, 2025, 05:14:17 am

Author Topic: Transformations HELP!  (Read 709 times)  Share 

0 Members and 1 Guest are viewing this topic.

DavidSheena

  • Victorian
  • Forum Regular
  • **
  • Posts: 67
  • Respect: 0
Transformations HELP!
« on: November 07, 2011, 04:51:23 pm »
0
I came across question where you had to apply a series of transformations to a equation. It read as follows:

The graph of the function with the rule y= x^(2/3) is transformed with the following:
-A dilation by a factor of 2 from the y-axis.
-A reflection in the x-axis
-A translation of +4 units parallel to the x-axis
-A translation of +1 units parallel to the y-axis.

My working was:

y=f(x) becomes, y=f(x/2), becomes, y= -f(x/2), becomes y= -f(x/2-4)+1

So my solution was y= -(x/2 -4)^(2/3) +1

But the answer is y= -((x-4)/2)^(2/3) +1

I thought mine would be correct since the translation was applied after the dilation and not before? Would appreciate if anyone could explain?
« Last Edit: November 07, 2011, 04:54:35 pm by DavidSheena »

dc302

  • Victorian
  • Part of the furniture
  • *****
  • Posts: 1031
  • Respect: +53
  • School: Melbourne High School
  • School Grad Year: 2009
Re: Transformations HELP!
« Reply #1 on: November 07, 2011, 04:55:30 pm »
0
You're very nearly right. The problem is when you applied the translation 4units in the x direction. When you do this, u have to change x to x-4.

So from y=-f(x/2), it becomes y = -f((x-4)/2)
2012-2015 - Doctor of Medicine (MD) @ UniMelb
2010-2011 - Bachelor of Science (BSc) majoring in Pure Mathematics @ UniMelb
2009 - VCE [99.70] -- Eng [43] - Methods [44] - Chem [44] - JapSL [45] - Spesh [45] - MUEP Jap [5.5]

DavidSheena

  • Victorian
  • Forum Regular
  • **
  • Posts: 67
  • Respect: 0
Re: Transformations HELP!
« Reply #2 on: November 07, 2011, 04:57:54 pm »
0
Oh, thank you! Just to clarify it's because your applying the translation to x, not to the whole thing inside the brackets?

dc302

  • Victorian
  • Part of the furniture
  • *****
  • Posts: 1031
  • Respect: +53
  • School: Melbourne High School
  • School Grad Year: 2009
Re: Transformations HELP!
« Reply #3 on: November 07, 2011, 05:08:46 pm »
0
You could think of it that way, yes.
2012-2015 - Doctor of Medicine (MD) @ UniMelb
2010-2011 - Bachelor of Science (BSc) majoring in Pure Mathematics @ UniMelb
2009 - VCE [99.70] -- Eng [43] - Methods [44] - Chem [44] - JapSL [45] - Spesh [45] - MUEP Jap [5.5]