Zero Cool

1 hour ago, studiot said:

Silvanus' answer is correct and follows the standard rule for differentiation of a power.

if  u=tp

then

dudt=pt(p−1)

 

 

 

Ok, so p = 2, and not 8, but since they are multiplied, that doesn't make sense to me. I have been out of school for a long time. Now (book is 75years old), would we use some parenthesis or something to show the 2 and the 4 are separate entities? 

This problem is from the book Calculus Made Easy by Silvanuws P. Thompson, copyright 1946 (3rd Ed.)

How on earth is answer not du/dt = 8u⁷?

The author uses a dot for showing both multiplication and as a divider between the ones column and the tenths column (see pics)

Thx

Thank you, I will look into those suggestions. 

I received an email from a man who uses a unique message in his signature. It is in the form of a math equation. To the left of the equal sign is S_W. I did some brief checking online and did not find an equation using S_W. I don't want to publish the entire equation so that someone else solves the message before me. Any help would be appreciated.

Possible clues:

1. he is a "petrophysical advisor" who works with an engineering firm

2. the equation is next to a picture of an oil derrick

If you have an idea what the equation might be used for but need an extra hint, I will provide more information.

Thank you.