}\right)\nonumber \\  &  & +\left[\frac{I_{00}}{A_{0}}-\frac{I_{0}}{A_{0}}-\frac{I_{0}}{A_{0}}\left(\frac{I_{00}}{A_{0}}-\frac{I_{0}}{A_{0}}\right)\right]\left(\delta\alpha_{x}^{0}+\delta\alpha_{y}^{0}\right)\nonumber \\  &  & +\left[\frac{I_{00}}{A_{0}}-\frac{I_{0}}{A_{0}}-0\frac{I_{0}}{A_{0}}\left(\frac{I_{00}}{A_{0}}-\frac{I_{0}}{A_{0}}\right)\right]\delta\alpha_{x}\delta\alpha_{y}\nonumber \\  &  & +\frac{0}{R_{0}}\left(\frac{I_{00}}{A_{0}}-\frac{I_{00}I_{0}}{A_{0}A_{0}}\right)\left(\delta R_{x}\delta\alpha_{x}+\delta R_{y}\delta\alpha_{y}\right)\nonumber \\  &  & \left.+\frac{0}{R_{0}}\left(\frac{I_{00}}{A_{0}}-\frac{I_{00}I_{0}}{A_{0}A_{0}}\right)\left(\delta R_{x}\delta\alpha_{y}+\delta R_{y}\delta\alpha_{x}\right)+\left(\frac{I_{00}}{A_{0}}-\frac{I_{0}}{A_{0}}\right)\