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2 years ago

An arithmetic sequence has this recursive formula

Mathematics

2 answers:

ycow [4]2 years ago

7 0

Answer:

$\text{The explicit formula is }a_n=7+(n-1)(-4)$

Option B is correct.

Step-by-step explanation:

Given the recursive formula of arithmetic sequence

$a_1=7$

$a_{n}=a_{n-1}-4$

we have to find the explicit formula for the above sequence.

$a_{n}=a_{n-1}-4$

$a_{n}-a_{n-1}=-4$

which is the common difference, d=-4

The explicit formula for A.P is

$a_n=a_1+(n-1)d$

$a_n=7+(n-1)(-4)$

Option B is correct.

OLga [1]2 years ago

6 0

Answer: B
This is because 7 is standing in place for a1 and -4 is standing in place for d in the explicit equation: an=a1+(n-1)d

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fenix001 [56]

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Step-by-step explanation:

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2 years ago

7.8c + 6p - 3.4c - 10

bija089 [108]

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2 years ago

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2 years ago

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topjm [15]

Answer:

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Step-by-step explanation:

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#events of interest/total number of events.

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Consider the case in which we choose two of the same color. That is, out of 5, we pick 2. The different ways of choosing 2 out of 5 is $\binom{5}{2}$ . Since we have 2 colors, we can either choose 2 of them blue or 2 of the red, so the total number of ways of choosing is just the double.

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