Q. Find the 8th term of the geometric sequence 2,6,18,…Answer:
Identify type of sequence: Identify the type of sequence.The given sequence is geometric because each term after the first is found by multiplying the previous term by a constant ratio.
Determine common ratio: Determine the common ratio r of the sequence.To find the common ratio, divide the second term by the first term.r=26=3
Use formula for nth term: Use the formula for the nth term of a geometric sequence.The nth term an of a geometric sequence can be found using the formula an=a1×r(n−1), where a1 is the first term and r is the common ratio.
Calculate 8th term: Calculate the 8th term using the formula. a8=2×38−1=2×37
Perform exponentiation: Perform the exponentiation. 37=3×3×3×3×3×3×3=2187
Multiply by first term: Multiply the result by the first term.a8=2×2187=4374