In the force method of analysis of indeterminate trusses, if the truss is indeterminate to degree one, the change in length of redundant, member due to unit force is found by using the formula where A is cross-sectional areaI – Moment of Inertian – force in the member due to unit load applicationN – force in the member due to actual loadE – Modulus of Elasticity

• A. \(\sum \frac{{nNL}}{{EI}}\)
• B. \(n\sum \frac{NL}{AE}\)
• C. \(\sum \frac{nNL}{AE}\)
• D. \(\sum \frac{NL}{AE}\)