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# Quick question about transformations. watch

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1. Graph transformations are the bane of my existence.
Possibly because I'm stupid, but ignoring that...

If you have f(x), will 3f(2x+1)+4 be:

Squash by ½ in x-direction (ie, halve all x-coordinates).
Shift by 1 in -ve x-direction (ie, -1 from all x-coordinates).
Stretch in y-direction by 3 (ie, triple all y-coordinates).
Shift up in y-direction (ie, +4 to all y-coordinates).

In that order?

:/

Thanks
2. I concur.
3. I concur.
4. thats right
5. (Original post by Rabite)
Graph transformations are the bane of my existence.
Possibly because I'm stupid, but ignoring that...

If you have f(x), will 3f(2x+1)+4 be:

Squash by ½ in x-direction (ie, halve all x-coordinates).
Shift by 1 in -ve x-direction (ie, -1 from all x-coordinates).
Stretch in y-direction by 3 (ie, triple all y-coordinates).
Shift up in y-direction (ie, +4 to all y-coordinates).

In that order?

:/

Thanks
y = 2x+1 is subbed into f(y), and f(y) subbed into z = 3f(y)+4

y causes a doubling of x-value, hence shrinking the x-direction, and it also increases the double of x by 1, so shifted into neg direction respective of the x-axis. The double of x increased by 1 is tripled, so that parallel to the y-axis, all values are stretched to a scalar of 3.
Finally the double of x increased by 1 and tripled by 3 is increased by 4, to produce a valuie which is translated by (0, 4) respective of the y-axis.

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Updated: June 11, 2006
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