I'm stuck on question #6 and I'm not sure if we went over this in class, since I wasn't here on Wednesday. I tried finding the instantaneous rate of change, but I keep getting the wrong answer. Any chance you could explain how to do this?

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Hey there! Here's a video that walks through the first question. A few notes:

1) The answer in the back of the book is wrong! I have no idea where their answer came from. I imagine this is not the only error, so let me know if you want me to check your answers.

2) I made a small mistake part way through the video, but later corrected it (I wrote 2x + 7 instead of 2x + 3).

I hope this helps!

Thanks for clearing this up! I got -0.31 for the slope too, but even the textbook corrections said something different. This is what I got for the rest of #6:

b) slope = 2.75; vertical asymptote: x = -5

c) slope = -46.0; vertical asymptote: x = -5/3

d) slope = -1.25; vertical asymptote: x = 6

Your answers are all correct! Just ignore the textbook answers and the "corrections." I don't know where their answers came from!

Same issues are happening with #7..

I used t = 60 and t = 10080 for #7 and got 0.003 kg/m^3 and approximately 0 kg/m^3, which don't match the solutions.

You're correct again!

Thanks again!