Hi. I have a huge problem and without solving it I can't move forward. I will appreciate any help. Having the stress tensor S: 163.666557052527 -63.0272557558942 0.000000000000000E+000 -63.0272557558942 70.3802282767392 0.000000000000000E+000 0.00000000000000 0.00000000000000 0.000000000000000E+000 σ11 - North, σ22 - East, σ33 - Down I have to calculate the normal stress and shear stress in slip direction for this focal mechanism α - strike = 315°, β - dip = 73°, and λ - rake(slip) = 55°. I think I know how to calculate the normal stress but I have no idea how to compute the shear stress in slip direction (55°) Please help!! M.