Graphing rates (1 Viewer)

[softwareAddict]

"The size of classes at a local TAFE college is decreasing and the rate at which this is happening is decreasing. Draw a graph to show this."
I'm getting a conflicting answer to the textbook, anyone care to share their answer?

 

[Carrotsticks]

Looks like the curve y=e^{-x}

 

[bedpotato]

Basically that question is saying that the size of the classes is decreasing at a decreasing rate. So: y' < 0 and y'' < 0. Just have to draw this.

 

[SharkeyBoy]

"The size of classes at a local TAFE college is decreasing and the rate at which this is happening is decreasing. Draw a graph to show this."
I'm getting a conflicting answer to the textbook, anyone care to share their answer?

The rate at which it is decreasing is decreasing i.e. the size of classes are getting smaller, but not as smaller anymore meaning like carrotsticks said: it looks like a y=e^(-x) curve

 

[softwareAddict]

I originally thought it was like y = e^(-x), but my textbook answers are saying its like what bedpotato said...
What do i do

 

[Carrotsticks]

Basically that question is saying that the size of the classes is decreasing at a decreasing rate. So: y' < 0 and y'' < 0. Just have to draw this.

The rate of it is decreasing, meaning the magnitude of the rate. You are interpreting it as the function decreasing at an increasing rate.

I originally thought it was like y = e^(-x), but my textbook answers are saying its like what bedpotato said...
What do i do

The answers are incorrect.

 

[asianese]

but as carrot said.

If it said: Decreasing at an increasing rate, then

 

[bedpotato]

Oh okay. Sorry, my bad.
Here:

 

[fatima96]

If its increasing the gradient is positive f'(x) > 0
If its decreasing the gradient is negative. f'(x) < 0
If the function is at a decreasing rate the function is concave down (i.e. f"(x) < 0)
If the function is at an increasing rate the function is concave up (i.e. f"(x) > 0 )