Learn the definition of a common ratio in a geometric sequence and the common ratio formula. Also, see examples on how to find common ratios in a...
Learn the definition of a common ratio in a geometric sequence and the common ratio formula. Also, see examples on how to find common ratios in a...
In a geometric sequence, the first term is 2 and the common ratio is 3. What is the 4th term? A. 18 B. 54 C. 16 D. 32 相关知识点: 试题来源: 解析 B。等比数列通项公式为 an = a1×r^(n - 1) ,将 a1 = 2,r = 3,n = 4 代入,可得 a4 = 2×3^(4 - 1) = 54 。
系列的无限的总和是16。[translate] aan infinite geometric sequence has commonratio r the second term of the series is -12. The sum of infinity of the series is 16. 一个无限几何学序列有commonratio系列的第二个期限是-12的r。 系列的无限的总和是16。[translate]...
试题来源: 解析 BLet y xr,z xr2.Since x,2y,3z are an arithmetic sequence,there is a common difference and we have 2xr-x=3xr2-2xr. Dividing through by x,we get2r-1=3r2-2ror,rearranging,(r-1)(3r-1)=0.Since we are given x≠y→r≠1,the answer is 1 (B) -3 ...
In a geometric sequence {an}, if the first term a1 = 2 and the common ratio q = 3, then the fifth term a5 can be expressed as which of the following? A. 2 * 3^3 B. 2 * 3^4 C. 2 * 3^5 D. 2 * 3^6 相关知识点: ...
Which best describes the common ratio for the sequence 9, 3, 1, 1/3? A. 3 B. -3 C. 1/3 D. -1/3 Sequence: In mathematics, we have two important types of sequences: Arithmetic sequence and Geometric sequence. In arithmetic sequence, the difference between...
10 terms. The first term is 2 and the common ratiois 4. If the product of the 10 terms is 2k, find the value of k. 相关知识点: 试题来源: 解析 100. 等比数列共有10项,其中首项是2,公比是4, 则a1=2, a2=2×4=23, a3=2×42=25, a4=2×43=27, a5=2×44=29, a6=2×45=211...
If the sum of the first three terms of a geometric sequence is 7 and the common ratio is 2, what is the first term? A. 1 B. 2 C. 3 D. 4 相关知识点: 试题来源: 解析 A。设首项为 a1 ,根据等比数列求和公式可得 a1 + a1 * 2 + a1 * 2^2 = 7 ,解得 a1 = 1 。B 选项 ...
The sum of the first 10 terms of a geometric sequence is 1023 and the common ratio is 2. Find the first term. A. 1 B. 2 C. 3 D. 4 相关知识点: 试题来源: 解析 A。解析:根据等比数列求和公式 Sn = a1(1 - q^n)/(1 - q),代入可得 a1 = 1。