On substituting equation(10.84) into the first set of equation (10.83), we get
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which can be can be written as

where
is the condensed stiffness matrix. Now internal DOFs could be eliminated from the shape assumed functions also. On substituting a , b , and c obtained from equation (10.67)into equation , we get

which could be simplified as
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with



Similarly, on substituting a , b and c obtained from equation(10.84) in equation (10.86), we get
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with


10.3.3 Weak Formulation of the Timoshenko Beam Element for the Dynamic Case
For dynamic case the shape functions derived in the previous section will still be valid and could take the following form
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