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NO LINKS!! Write an expression for the nth term of the geometric sequence. Then find the indicated term.

a1= 3, r = √(2), n = 10

a_n =
a_10=

User Microfed
by
3.7k points

2 Answers

4 votes

Answer:


a_n=3\left(√(2)\right)^(n-1)


a_(10)=48 √(2)

Explanation:


\boxed{\begin{minipage}{5.5 cm}\underline{Geometric sequence}\\\\$a_n=ar^(n-1)$\\\\where:\\\phantom{ww}$\bullet$ $a$ is the first term. \\\phantom{ww}$\bullet$ $r$ is the common ratio.\\\phantom{ww}$\bullet$ $a_n$ is the $n$th term.\\\phantom{ww}$\bullet$ $n$ is the position of the term.\\\end{minipage}}

Given:


  • a = 3

  • r = √(2)

  • n=10

Substitute the given values of a and r into the formula to create an equation for the nth term:


a_n=3\left(√(2)\right)^(n-1)

To find the 10th term, substitute n = 10 into the equation:


\implies a_(10)=3\left(√(2)\right)^(10-1)


\implies a_(10)=3\left(√(2)\right)^(9)


\implies a_(10)=3 \cdot 2^{(9)/(2)}


\implies a_(10)=3 \cdot 2^{4+(1)/(2)}


\implies a_(10)=3 \cdot 2^(4) \cdot 2^{(1)/(2)}


\implies a_(10)=3 \cdot 16 \cdot √(2)


\implies a_(10)=48 √(2)

User Kevin Glynn
by
4.0k points
5 votes

Answer:


tn = {3 * √(2) }^(n - 1)

Explanation:

since it is geometric sequence we will use the formula


tn = {ar}^(n - 1)

n = 10

r = √2

a = 3

lets first see the result of the 10th term


t10 = {ar}^(10 - 1)


t10 = {ar}^(9)


t10 = {3 * √(2) }^(9)

t10 = 3 × 22.63

t10 = 67.89

approximately 68

t10 = 68

for the nth term

Tn = ar^n–1


tn = {3 * (√(2) })^(n - 1)

i hope this helps

User Pi Horse
by
3.7k points