Choose the function whose graph is given by: (graph shown below)
Do you remember how a horizontal shift is applied? What it does to the x coordinate?
Let me look at my notes and see if I wrote down something like that >.<
The value of this function is 1 at x=1. Adding 1 to x has the effect of shifting the function left (or the y-axis to the right, whichever way you best remember). Subtracting 1 from x has the effect of shifting the function right (or the y-axis left).
Then it would be A?
As lars said, adding 1 to x would shift it to the left. Is that what's happening in the picture? Or is it shifted to the right? :3
It's being shifted to the right. >.<
To shift, you do the opposite to your coordinate. That's how I like to remember it at least. We want to shift in the positive direction? Ok we subtract. We want to shift in the negative direction? Ok we add.
I'm writing that down hahah. xD Okay, so now it would either be B or D, right?
Yes, B or D.
How do you narrow it down to whether it's the one with parenthesis or not?
\[\Large\rm y=\cos x\]So if I do this,\[\Large\rm y+1=\cos x\]And then subtract 1 from each side,\[\Large\rm y=\cos x-1\]Did I mess with the x or the y coordinate initially?
You moved the x and kept the y alone. So you messed with the x?
Nooo. :o Look back at the first step I made. I replaced y with y+1. I messed with the y, yes?
In that case, yep you messed with the y. ;o
Messing with the y results in a `VERTICAL` shift. (Up or Down).
\[\Large\rm \color{orangered}{y}=\cos (x)\]If we had wanted to shift our function DOWN then this would have worked out nicely,\[\Large\rm \color{orangered}{y+1}=\cos (x)\]\[\Large\rm y=\cos(x)-1\qquad\leftarrow bad~:o\] But instead:\[\Large\rm y=\cos (\color{orangered}{x})\]We want to mess with the x to make it shift to the right.\[\Large\rm y=\cos (\color{orangered}{x-1})\]
well shiz. That explains the parenthesis now.
lol
I think I got this (kinda) now I gotta remember this for the next time I mess with this quiz. ahah. -__-
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