Inverse
try multipy by conjugate:
(e + ex + ey + exy)( e + ex + ey - exy)
a.e | a.ex | a.ey | -a.exy | |
b.e | e | ex | ey | -exy |
b.ex | ex | e | exy | -ey |
b.ey | ey | -exy | e | +ex |
b.exy | exy | -ey | ex | e |
e = 4e
ex = 4ex
ey = 0
exy = -exy+exy-exy+exy =0
a.e | a.ex | a.ey | a.exy | |
b.e | e | ex | ey | exy |
b.ex | ex | e | exy | ey |
b.ey | ey | -exy | e | -ex |
b.exy | exy | -ey | ex | -e |