How do you write a rule for the nth term of the geometric term and then find $a_6$ given $r=1/10, a_2=4$ ?

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Answer 1 · 2017-03-10T16:47:05

$T_6 = 1/2500 = 0.0004$

In a GP, each term is multiplied by the common ratio to get the next term in the sequence.

We do not have the first term, $a$ , but we can find it from $T_2$

$T_2 = 4 = a xx 1/10$

$a = 4 xx 10 = 40$

$T_n = a r^(n-1)$

$T_n = 40 * (1/10)^(n-1)$

$T_6 = 40 *(1/10)^5$

$T-6 = 40 xx 1/10^5$

$T_6 = 1/2500 = 0.0004$

How do you write a rule for the nth term of the geometric term and then find a_6a_6 given r=1/10, a_2=4r=1/10, a_2=4?