Find the Jacobian matrix for the nine-node quadrilateral element shown in Fig. P9.18. What is the determinant of the Jacobian matrix?

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This problem is similar to one in Problem 9.10 (see Figure P9.10), except that it is a nine-node element used here. Once again we note that the node numbering used in Figure P9.14 is different from that used for the master element in Figure 9.6.