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2 years ago

What is the first term for an arithmetic sequence with a12 = 56 and a21=101?

1 answer:

4 0

The first term is -43.

Explanation:

an = a + (n - 1)d

a12 = a + 11d = 56, first equation
a21 = a + 20d = 101, second equation

Subtract the second equation from the first equation, cancelling +a and -a
11d - 20d = 56 - 101
-9d = -45
d = 5

Subtitute d into the first equation
a + 99 = 56
a = -43

a refers to the first term, hence the first term is -43.

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iragen [17]

Answer:

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Step-by-step explanation:

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2 years ago

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Natalka [10]

None of these. All of these functions are defined as ratio of trigonometric functions.

Trigonometric functions have infinite zeroes, so when you put them in the denominator, they lead to infinitely many points of ill-definition.

Specifically, we have:

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$\sin(x)=0\iff x=k\pi, k\in\mathbb{Z}$

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$\tan(x) = \dfrac{\sin(x)}{\cos(x)}$

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which is undefined at

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2 years ago

Using coal, steam, and _____, the fischer-tropsch procedure converts coal into a liquid fuel.

ANTONII [103]

Answer:

Using coal, steam, and <u>OXYGEN,</u> the fischer-tropsch procedure converts coal into a liquid fuel.

Step-by-step explanation:

A series of chemical reactions in which hydrogen and carbon monoxide converges into liquid hydrocarbons by using a metal catalyst. This process is called The Fischer-Tropsch process.

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2 years ago

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lana [24]

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2 years ago

Resultado de esta cuenta Explicada cuenta completa:<br><br>(6+3)²=

Mumz [18]

81 is the correct answer

hope it helps you have a good day

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2 years ago