Question about area between curves (integral calc textbook q

[quicksilver123]

hi please refer to the inline image:
What do the stars mean? I can't find a reference or definition elsewhere in my textbook...

 

[blue_leaf77]

Just for denoting the sampled points, as the text says.

 

[quicksilver123]

Oh I see so this is not some convention, but merely indicating the points on the graph?
I've just never seen an asterisk used before, they usually use a different letter value (a, b, c) to designate constants.
Can anyone confirm the previous poster?

 

[elements]

Yeah, it's just for sampling the points. My textbooks do it as well

 

[blue_leaf77]

Oh I see so this is not some convention, but merely indicating the points on the graph?
I've just never seen an asterisk used before, they usually use a different letter value (a, b, c) to designate constants.
Can anyone confirm the previous poster?

Of course it depends on the context. When you start learning complex number you will see that an asterisk is often understood to represent the so-called complex conjugation of a complex number. At least that's the tradition in physics textbooks, among mathematicians as far as I know they use an overbar to represent a complex conjugation instead of an asterisk.

 

[mathwonk]

the best way to confirm this is to go back and read closely the definition of the integral via limits of Riemann sums, possibly in chapter 5. Almost certainly this was explained in the book.

 

[MidgetDwarf]

I believe, the asterix is used to denote sample points in your book. Does your book define a Net on an interval? The Mesh of a Net?