Q. Find the 2nd term in the expansion of (x+2)4 in simplest form.Answer:
Use Binomial Theorem: To find the 2nd term in the expansion of (x+2)4, we will use the binomial theorem. The binomial theorem states that (a+b)n expands to a series of terms of the form C(n,k)⋅a(n−k)⋅bk, where C(n,k) is the binomial coefficient, which can be calculated as k!(n−k)!n!. The 2nd term corresponds to k=1.
Calculate Binomial Coefficient: First, we calculate the binomial coefficient for n=4 and k=1. C(4,1)=1!(4−1)!4!=1!3!4!=(1×3×2×1)(4×3×2×1)=14=4.
Apply Coefficient to Terms: Next, we apply the binomial coefficient to the terms of (x+2). The 2nd term will be C(4,1)×x(4−1)×21=4×x3×2.
Simplify Expression: Now, we simplify the expression. 4×x3×2=8×x3.
Final Result: The 2nd term in the expansion of (x+2)4 in simplest form is therefore 8×x3.
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