Q. Find the 6th term in the expansion of (5x+3)6 in simplest form.Answer:
Use Binomial Theorem: To find the 6th term in the expansion of (5x+3)6, we will use the binomial theorem. The binomial theorem states that the nth term in the expansion of (a+b)m is given by the formula C(m,n−1)⋅am−n+1⋅bn−1, where C(m,n−1) is the binomial coefficient, which can be calculated as (m−n+1)!⋅(n−1)!m!.
Identify a, b, m: First, we need to identify 'a', 'b', and 'm' in our expression (5x+3)6. Here, 'a' is 5x, 'b' is b0, and 'm' is b2. We are looking for the b2th term, which means 'b4' is b2.
Calculate Binomial Coefficient: Now we calculate the binomial coefficient for the 6th term, which is C(6,6−1) or C(6,5). The binomial coefficient C(6,5) is calculated as 1!×5!6!=1×1206=1206=201. However, this is a mistake because the correct calculation should be 1!×5!6!=1×1206=1206=201 is incorrect as 1!×5!6! is actually 1×1206=1206=201 is incorrect as 1!×5!6! is actually 16=6.
More problems from Partial sums of geometric series