We must show that and are NOT isomorphic. Consider the mapping . Then we have which can be written as . So, which is the same as . We can split this apart to get . This shows that . But nothing in squares to . Therefore they are not isomophic.
We must show that and are NOT isomorphic. Consider the mapping . Then we have which can be written as . So, which is the same as . We can split this apart to get . This shows that . But nothing in squares to . Therefore they are not isomophic.