Answer with explanation:
- It is given that {u,v} be a linearly independent set of a set S.
This means that there exist constant a,b such that if:
au+bv=0
then a=b=0
- Now we are asked to prove that:
{u+v,u-v} is a linearly independent set.
Let us consider there exists constant c,d such that:
c(u+v)+d(u-v)=0
To show: c=d=0
The expression could also be written as:
cu+cv+du-dv=0
( Since, using the distributive property)
Now on combining the like terms that is the terms with same vectors.
cu+du+cv-dv=0
i.e.
(c+d)u+(c-d)v=0
Since, we are given that u and v are linearly independent vectors this means that:
c+d=0------------(1)
and c-d=0 i.e c=d-----------(2)
and from equation (1) using equation (2) we have:
2c=0
i.e. c=0
and similarly by equation (2) we have:
d=0
Hence, we are proved with the result.
We get that the vectors {u+v,u-v} is linearly independent.