Linear algebra, field morphisms and linear independence

Click For Summary
The discussion centers on proving the linear independence of field morphisms f1, f2, ..., fn from K to L, given that each morphism is distinct. The injectivity of these morphisms, indicated by their kernels being zero, is a crucial point in the proof. Participants suggest starting with small cases, such as n=1 and n=2, to develop a general argument or use induction for larger n. It is also noted that the condition f_i ≠ 0 is necessary for the proof. The conversation emphasizes the importance of understanding linearity and injectivity in establishing the desired result.
mariang
Messages
1
Reaction score
0

Homework Statement


Let f1,f2, ..., fn : K -> L be field morphisms. We know that fi != fj when i != j, for any i and j = {1,...,n}. Prove that f1,f2, ..., fn are linear independent / K.

Homework Equations


f1, ..., fn are field morphisms => Ker (fi) = 0 (injective)

The Attempt at a Solution


I tried to use the linearity and the injectivity but i got stuck.
 
Physics news on Phys.org
mariang said:

Homework Statement


Let f1,f2, ..., fn : K -> L be field morphisms. We know that fi != fj when i != j, for any i and j = {1,...,n}. Prove that f1,f2, ..., fn are linear independent / K.

Homework Equations


f1, ..., fn are field morphisms => Ker (fi) = 0 (injective)

The Attempt at a Solution


I tried to use the linearity and the injectivity but i got stuck.
In such cases it is often helpful to start with ##n=1## and ##n=2## to see how possible arguments work. From there one can either proceed by a general ##n## or per induction. I assume we also have to require ##f_i \neq 0\,.##
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

Similar threads

  • · Replies 31 ·
2
Replies
31
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 8 ·
Replies
8
Views
13K
  • · Replies 28 ·
Replies
28
Views
4K
  • · Replies 12 ·
Replies
12
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K