That is geometric sequence where firs term a1 = - 2 and common ratio r = - 2
The n-th term of a geometric sequence:
an = a1 ∙ r ⁿ ⁻¹
In this case:
a20 = - 3 ∙ ( - 2 ) ²⁰ ⁻¹ = - 3 ∙ ( - 2 ) ¹⁹ = - 3 ∙ ( - 1 ∙ 2 ) ¹⁹ =
= - 3 ∙ ( - 1 ) ¹⁹ ∙ ( 2 ) ¹⁹ =
- 3 ∙ ( - 1 ) ∙ ( 2 ) ¹⁹ = 3 ∙ 524 288 = 1 572 864
What is the 20th term of the sequence -3, 6, -12, 24
The answer is 1,572,864 i just need to know the math in order to obtain the answer.
3 answers
Find the 30th term of the geometric sequence 3, 6, 12, 24, . . . ?
Find the 30th term of the geometric sequence 3, 6, 12, 24, . . . ?