What is a Basis of a Vector Space and How to Find Another Basis?

Coolster7
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Homework Statement



There is a standard basis, B = (1; z; z^2; z^3; z^4) where B is the basis of a R4[z] of real polynomials of at most degree 4.

I need to find another basis B' for R4[z] such that no scalar multiple of an
element in B appears as a basis vector in B' and also prove that this B' is a basis.

Can any help with this please?

Homework Equations





The Attempt at a Solution



I could only think to do a basis B'=(0,1,z,z^2,z^3) but no sure if this is correct.
 
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Coolster7 said:

Homework Statement



There is a standard basis, B = (1; z; z^2; z^3; z^4) where B is the basis of a R4[z] of real polynomials of at most degree 4.

I need to find another basis B' for R4[z] such that no scalar multiple of an
element in B appears as a basis vector in B' and also prove that this B' is a basis.

Can any help with this please?

Homework Equations





The Attempt at a Solution



I could only think to do a basis B'=(0,1,z,z^2,z^3) but no sure if this is correct.
No, it isn't correct. The 0 vector can never be a vector in a basis for a vector space.

Here's a hint: the function 1 + z is not a linear multiple of any of the vectors in B, right?
 
Mark44 said:
No, it isn't correct. The 0 vector can never be a vector in a basis for a vector space.

Here's a hint: the function 1 + z is not a linear multiple of any of the vectors in B, right?

So you could have B' = (1+z, 1+z^2, 1+z^3, 1+z^4, 1+z^5) for example or would this not work because the highest degree for R4[z] is 4?

Thanks for your reply.
 
Right, you can't have 1 + z5. Can't you think of any other combinations besides adding 1 to another vector in the basis?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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