M25008PP8

# M25008PP8 - Mathematics 250 Fall 2008 Proof Practice 8 Let...

This preview shows pages 1–2. Sign up to view the full content.

Mathematics 250 Fall 2008 Proof Practice # 8 Let U be an open domain in R m . Let f : U R k and g : U R be functions. Define f g to be the function from U to R k + whose first k coordinates are the coordinates of f , and whose last coordinates are the coordinates of g . In particular, if f and g are scalar-valued, i.e., k = = 1, then ( f g )( u ) = f ( u ) g ( u ) maps U to R 2 . a) Show that if f and g are continuous, then f g is continuous. b) Combine Proof Practices # 2 and # 7 with part a) to show that, if f and g are continuous scalar- valued functions on U , then f + g and fg are also continuous. (This of course can be shown directly. However, you are asked to base your argument on the indicated results.) Response: a) To show that f g is continuous, one can appeal to the result, proved in class, that a vector-valued function F = F 1 F 2 F 3 . . . F n : U R n is continuous if and only if each component F i of F is continuous. By definition of f g

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern