Can somebody help point me in the right direction so that I can understand these 3 questions a little more, i'm supposed to find proofs.
Thanks
Is that actually copied from your book? It's terrible proofreading- they have "z.t" where they mean "z, t" and "proof that" instead of "prove that".
You are first asked to prove that $\displaystyle G\oplus H= R^4$. What is the definition of the left side?
Start by finding a basis for each vector space.