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A2 c3) transformation question!

Hi

I'm a bit confused when it comes to transforming graphs..

if for example ln(16x^2+5) was translated by (-3) on the x axis

how do we work that out?

Your help is greatly appreciated

thank you!
Reply 1
Original post by liemluji
Hi

I'm a bit confused when it comes to transforming graphs..

if for example ln(16x^2+5) was translated by (-3) on the x axis

how do we work that out?

Your help is greatly appreciated

thank you!


Well, you should know that if it gets translated three to the left then you need f(x+3)f(x+3) where f(x)=ln(16x2+5)f(x) = \ln (16x^2 + 5).

So, to get f(x+3)=ln(16(x+3)2+5)f(x+3) = \ln (16(x+3)^2 + 5).
Original post by liemluji
Hi

I'm a bit confused when it comes to transforming graphs..

if for example ln(16x^2+5) was translated by (-3) on the x axis

how do we work that out?

Your help is greatly appreciated

thank you!


The change is applied to the "x". It may help to put parentheses around the x.

So, ln(16(x)^2+5)

Translate by -3, i.e. shift left by 3, so we change x to x+3, to get:

ln(16(x+3)^2+5)

and simplify as desired.

Edit: ninja'd again.
(edited 7 years ago)
Reply 3
Original post by Zacken
Well, you should know that if it gets translated three to the left then you need f(x+3)f(x+3) where f(x)=ln(16x2+5)f(x) = \ln (16x^2 + 5).

So, to get f(x+3)=ln(16(x+3)2+5)f(x+3) = \ln (16(x+3)^2 + 5).



Oh right it was so easy

Thank you anyways!
Original post by liemluji
Oh right it was so easy


In which case try f(x)=x23xf(x)=x^2-3x with the same shift as before.
Reply 5
Original post by ghostwalker
In which case try f(x)=x23xf(x)=x^2-3x with the same shift as before.


would that be (x+3)^2-3(x+3) ?
Original post by liemluji
would that be (x+3)^2-3(x+3) ?


Yep.

On reflection it wasn't the best example. Below is the point I was trying to make. But looks as if you have it nailed.

If you have -x say, then a lot of people make the mistake of converting it to -x+3, when in fact it's -x = -(x) gives -(x+3) = -x-3
Reply 7
Original post by ghostwalker
Yep.

On reflection it wasn't the best example. Below is the point I was trying to make. But looks as if you have it nailed.

If you have -x say, then a lot of people make the mistake of converting it to -x+3, when in fact it's -x = -(x) gives -(x+3) = -x-3


oh right thank you so much

you've helped me more than you had to!
Reply 8
Original post by liemluji
oh right thank you so much

you've helped me more than you had to!


Late, but have a look at this.
Mess around with the slider if you want!
Hope it kinda helps!
Reply 9
Original post by P____P
Late, but have a look at this.
Mess around with the slider if you want!
Hope it kinda helps!


thank you!

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