00:01
Hello students, in this problem let us take w is equal to ab where a and b belongs to integers.
00:12
Consider this as equation number one.
00:15
We have to prove w is a subspace of r square.
00:27
If w is a subspace, then the three conditions should be satisfied.
00:36
First one, w not equal to second one, let x comma y belongs to w, then x plus y also belongs to w.
00:49
And third one is, let us take alpha is any real number which should be belongs to field and x belongs to w, which implies alpha x belongs to w.
01:01
If the three conditions are satisfied, then we can easily prove w is a subspace.
01:08
For the first condition, if we take a equal to 0 and b equal to 0, then 0 0 belongs to w, which means that w not equal to empty.
01:25
Therefore, the first condition is satisfied.
01:27
For the second condition, let x comma y belongs to w and let x is equal to ab and y is equal to cd and x plus y is equal to a plus c, b plus d.
01:47
A, b, c, d are integers...