Q. Find the 2 nd term in the expansion of (4x+7y)5 in simplest form.Answer:
Use Binomial Theorem: To find the 2nd term in the expansion of (4x+7y)5, we will use the binomial theorem. The general term in the expansion of (a+b)n is given by T(k+1)=C(n,k)⋅a(n−k)⋅bk, where C(n,k) is the binomial coefficient "n choose k". For the 2nd term, k=1.
Calculate Binomial Coefficient: Calculate the binomial coefficient for the 2nd term, which is C(5,1). C(5,1)=1!∗(5−1)!5!=15=5.
Apply General Term Formula: Now, plug in the values into the general term formula for k=1. T(2)=C(5,1)×(4x)(5−1)×(7y)1.
Simplify Expression: Simplify the expression. T(2)=5×(4x)4×(7y)=5×256x4×7y=1280x4×7y.
Final Simplified Form: Multiply the constants to get the final simplified form of the 2nd term. T(2)=1280×7×x4×y=8960x4y.
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