Transformations of Functions
A bit of confusion I am having with compression and expansion.
Original was a -5.
Compress horizontally by a factor of 1/5. New equation: y=f(5x)
Expand horizontally by a factor of 3. New equation: y=f(1/3x)
Compress horizontally by a factor of 1/4. New equation: y=(4x)
Compress horizontally by a factor of 2/9. New equation: y=(-9/2x)
Basically what I am asking is shouldn't number 3 be EXPAND because it is a positive? It might be an error on my sheet but it is printed from my teacher, so I am (Headbang) right now.
Oh and shouldn't number 1's new equation be: y=f(-5x)?
It would make sense if expand for positive and compress for negative.. unless this idea is wrong..