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3 years ago

13

How do I write a recursive formula for this sequence? 2, 6, 18, 54, 162, ... I already know the common difference is x3.

1 answer:

dmitriy555 [2]3 years ago

4 0

For the sequence 2, 6, 18, 54, ..., the explicit formula is: an = a1 ! rn"1 = 2 ! 3n"1 , and the recursive formula is: a1 = 2, an+1 = an ! 3 . In each case, successively replacing n by 1, 2, 3, ... will yield the terms of the sequence. See the examples below.

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84m2

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mary's job pays her $8.75 per hour which of the following expressions best represents her total earnings if she works two hours

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The value of y varies directly as x with a constant variation of 2 what is the value of y when x is 6?

sp2606 [1]

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The value of y is 12

Step-by-step explanation:

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8 0

3 years ago

The first term of a geometric sequence is 15, and the 5th term of the sequence is <img src="https://tex.z-dn.net/?f=%5Cfrac%7B24

sladkih [1.3K]

The geometric sequence is $15,9,\frac{27}{5},\frac{81}{25}, \frac{243}{125}$

Explanation:

Given that the first term of the geometric sequence is 15

The fifth term of the sequence is $\frac{243}{125}$

We need to find the 2nd, 3rd and 4th term of the geometric sequence.

To find these terms, we need to know the common difference.

The common difference can be determined using the formula,

$a_n=a_1(r)^{n-1}$

where $a_1=15$ and $a_5=\frac{243}{125}$

For $n=5$ , we have,

$\frac{243}{125}=15(r)^4$

Simplifying, we have,

$r=\frac{3}{5}$

Thus, the common difference is $r=\frac{3}{5}$

Now, we shall find the 2nd, 3rd and 4th terms by substituting $n=2,3,4$ in the formula $a_n=a_1(r)^{n-1}$

For $n=2$

$a_2=15(\frac{3}{5} )^{1}$

$=9$

Thus, the 2nd term of the sequence is 9

For $n=3$ , we have,

$a_3=15(\frac{3}{5} )^{2}$

$=15(\frac{9}{25} )$

$=\frac{27}{5}$

Thus, the 3rd term of the sequence is $\frac{27}{5}$

For $n=4$ , we have,

$a_4=15(\frac{3}{5} )^{3}$

$=15(\frac{27}{25} )$

$=\frac{81}{25}$

Thus, the 4th term of the sequence is $\frac{81}{25}$

Therefore, the geometric sequence is $15,9,\frac{27}{5},\frac{81}{25}, \frac{243}{125}$

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3 years ago

8-5(3x-7) i need help

MArishka [77]

Answer:

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is the answer

4 0

3 years ago

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