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3 years ago

What is ∑n=15[5(−2)n−1] equal to?

Mathematics

1 answer:

kicyunya [14]3 years ago

6 0

Answer:

Although the notation is sloppy, I will assume based on former questions of the same that "∑n=15[5(−2)^n−1]" translates mathematically to . Please correct me, though, if this in incorrect.

Anyway, there is neat formula that will deal with question very quickly. It is the following:

Sn is the sum of the geometric series

a1 is the first term in the series

r is the common ratio

n is the number of terms in the finite geometric series

Let's use this formula to our advantage! However, there are two variables that we do not know: a1 and n. Let's start with a1.The first term in the series is when n=1, so let's determine what that is.

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What is the quotient of StartFraction negative 8 x Superscript 6 Baseline Over 4 x Superscript negative 3 Baseline EndFraction?

scZoUnD [109]

Answer:

Option D.

Step-by-step explanation:

We need to find the quotient of

$\dfrac{-8x^6}{4x^{-3}}$

It can rewritten as

$\dfrac{-8}{4}\times \dfrac{x^6}{x^{-3}}$

$-2\times x^{6-(-3)}$ $[\because \dfrac{a^m}{a^n}=a^{m-n}]$

$-2x^{6+3}$

$-2x^{9}$

The required expression is $-2x^{9}$ .

Therefore, the correct option is D.

8 0

3 years ago

find the area of the regular polygon with the given apothem a and side length s. a=28. s=18.2 round to the nearest decimal place

miskamm [114]

The formula for finding the area of any regular polygon if you know the length of one side and the apothem: A = (n × s × a)2 A = ( n × s × a ) 2 , where n is the number of sides, s is the length of one side, and a is the apothem.

6 0

3 years ago

Help please!!!! I will really appreciate it please help

Scorpion4ik [409]

Answer:

Correct answer is x = 28°

Step-by-step explanation:

Okay we know Angle A is 2x + 2

Angle B is 90

Angle C is 180 - 148 = 32 ( straight line angle is 180)

Sum of all angles should be 180 in a triangle

which means

A + B + C = 180

2x + 2 + 32 +90 = 180

2x + 124 = 180

2x = 180-124

2x = 56

x = 56/2

x = 28

4 0

3 years ago

Read 2 more answers

Which function can be used to represent the graphed geometric sequence? f(x) = 80(One-fourth) Superscript x minus 1 f(x) = 320(O

telo118 [61]

You can use the formula for getting the xth term of a geometric sequence for the graphed points.

The function that represents the graphed geometric sequence is given by

Option A: $f(x) = 80 \times (\dfrac{1}{4})^{x-1}$

<h3>What is a geometric sequence and how to find its xth terms?</h3>

There are three parameters which differentiate between which geometric sequence we're taking about.

The first parameter is the initial value of the sequence.
The second parameter is the quantity by which we multiply previous term to get the next term.
The third parameter is the length of the sequence. It can be finite or infinite.

Suppose the initial term of a geometric sequence is $a$ and the term by which we multiply the previous term to get the next term is $r$