二.单元分析 8求图示结构2单元的坐标转换矩阵中的元素T1212 cos(-45°)=√2/2 a 12=sm(-45)=-√2/2 cosa sin a0 0 00 sin a cosa 00 00 00 00 cosa sin a O 0 0-sin a cosa 0 000二. 单元分析 sin( 45 ) 2 / 2 cos( 45 ) 2 / 2 1 2 1 1 = − = − = − =   T T 8.求图示结构2单元的坐标转换矩阵中的元素 11 12 T ,T                       − − = 0 0 0 0 0 1 0 0 0 sin cos 0 0 0 0 cos sin 0 0 0 1 0 0 0 sin cos 0 0 0 0 cos sin 0 0 0 0         e T 1 2 a a a