Q. Find the 2 nd term in the expansion of (2x+3)6 in simplest form.Answer:
Use Binomial Theorem: To find the 2nd term in the expansion of (2x+3)6, we will use the binomial theorem. The general form of the k-th term in the expansion of (a+b)n is given by T(k)=C(n,k−1)⋅a(n−k+1)⋅b(k−1), where C(n,k) is the binomial coefficient "n choose k". For the 2nd term, k=2.
Calculate Binomial Coefficient: First, we calculate the binomial coefficient for the 2nd term, which is C(6,2−1)=C(6,1). The binomial coefficient C(n,k) is calculated as k!⋅(n−k)!n!, where "!" denotes factorial.
Correct Factorial Calculation: Calculating C(6,1) gives us (1!∗(6−1)!)6!=(1∗5!)6=(1∗120)6=1206=201. This is incorrect because we made a mistake in the factorial calculation. The correct calculation should be (1∗5!)6=(1∗120)6=1206=201, which simplifies to 6.
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