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HELP ASAP... I DONT UNDERSTAND AND HAVE A TEST TMMRW! explain & answer

*will give crown to first person who helps*

HELP ASAP... I DONT UNDERSTAND AND HAVE A TEST TMMRW! explain & answer *will give-example-1
User Linrongbin
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2 Answers

2 votes

Answer:

The pattern is that each number is being multiplied by 3.

a: x * 3

b: 54 = 2 + (4 - 1)17.3

Explanation:

a: x * 3

b: it's basically asking you to put it in function form and the image i attached explains it.

an = a + (n - 1)d

an = 54 because it's the last number

a = 2 because it's the first number

n = 4 because that's how many numbers there are in the sequence

d = 17.3, when you subtract the value between each number you get 52 and then divide that buy 3 and you get 17.3

subtract between the values:

6 - 2 = 4

18 - 6 = 12

54 - 18 = 36

then add all the numbers:

4 + 12 + 36 = 52

then divide by 3 since you subtracted 3 times:

52 / 3 = 17.3

HELP ASAP... I DONT UNDERSTAND AND HAVE A TEST TMMRW! explain & answer *will give-example-1
User Moss Collum
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7.1k points
0 votes

Answer:

Part a is
A_n=2*3^(n-1)

Explanation:

Step 1: Recall

Okay, so the formula for an explicit formula is
A_(n) = a r^(n-1).

Step 2: Plug values in


A_n This is the term you are solving for? In this case, you are not solving for a time.
a In this problem is the first term. In this case, two so let's plug that in.
A_n = 2r^(n-1)

The next time is
r . r for ratio or standard ratio. The common ratio is the number that is being multiplied or added. In this equation, each number is tripled so we can plug in 3 for r.
A_n = 2*3^(n-1). So this is your explicit formula.

I forgot function form.. But I hope this poster my teacher made for me can help!

I think I used the wrong formula...

HELP ASAP... I DONT UNDERSTAND AND HAVE A TEST TMMRW! explain & answer *will give-example-1
User Noelyahan
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7.3k points