By applying basic property of Geometric progression we can say that sum of 15 terms of a sequence whose first three terms are 5, -10 and 2 is $\sum_{n=4}^{15} 5(-2)^{n-1}$$$

<h3>What is sequence ?</h3>

Sequence is collection of numbers with some pattern .

Given sequence

$a_{1}=5\\\\a_{2}=-10\\\\\\a_{3}=20$

We can see that

$\frac{a_1}{a_2}=\frac{-10}{5}=-2\\$

and

$\frac{a_2}{a_3}=\frac{20}{-10}=-2\\$

Hence we can say that given sequence is Geometric progression whose first term is 5 and common ratio is -2

Now $n^{th}$ term of this Geometric progression can be written as

$T_{n}= 5\times(-2)^{n-1}$

So summation of 15 terms can be written as

$\sum_{n=4}^{15} T_{n}\\\\$\\$\sum_{n=4}^{15} 5(-2)^{n-1}$$$

By applying basic property of Geometric progression we can say that sum of 15 terms of a sequence whose first three terms are 5, -10 and 2 is $\sum_{n=4}^{15} 5(-2)^{n-1}$$$

To learn more about Geometric progression visit : brainly.com/question/14320920

8 0

2 years ago

HERE HELP PLEASE<br> plzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

nevsk [136]

A function is a relation for which each value from the set the first components of the ordered pairs is associated with exactly one value from the set of second components of the ordered pair.

3 0

2 years ago

Help me.. please and ty.

makkiz [27]

Answer:

Step-by-step explanation:

$y = \frac{-1}{5}x - 4\\\\Plugin x = 0 , y = 0 - 4\\\\ y = -4\\\\(0 , -4)\\\\Plugin x = 5, y =\frac{-1}{5}*5-4 = -1-4=-5\\\\(5 , -5)\\\\Plugin x = -5, y =\frac{-1}{ 5}*(-5)-4=1 - 4 = -3\\(-5, -3)$

Plot the points(0 ,-4) , (5 , -5) and (-5 , -3 ) in the graph and join the points.

5 0

3 years ago

What is the value of the expression 8-(2to the 3rd Power+48)divided by 8

dalvyx [7]

8-(8+48) = -48 then divide that by 8 and you get -6 as your result

8 0

2 years ago