Question

Algebra II Sigma Notation help please!

Answer 1

@ranga

Answer 2

@wolf1728

Answer 3

@shamil98 @ehuman

Answer 4

The sigma notation means summation. The variable "i" runs from 1 to 5. Put i = 1and get the first term. For example, the first term is: 3 * (-4)^(1-1) = 3 * (-4)^0 = 3 * 1 = 3

Put i = 2, 3, 4 & 5 and evaluate the other terms. Then add them all up.

Answer 5

Isn't there some kind of formula to use for this? The rest of the questions used a formula

Answer 6

There is a formula for the sum of a geometric progression. You can plug in the numbers into the formula and calculate the sum. But I don't think that is what they want you do here. If that is what they want why use sigma notation and ask you to explain the necessary steps?

Answer 7

I'm not sure... If you tell me the formula, I would know if it seems familiar...

Answer 8

The sum of the first n terms of a GP is: a * (1 - r^n) / (1 - r)

Answer 9

I have something very similar to that... \[S _{i}=\frac{ a _{1} }{ 1-r }\]

Answer 10

Where did you get that from? That does not look right.

Answer 11

that's from my lesson notes

Answer 12

that's the closest thing to the formula you gave me

Answer 13

On the left side you have S subscript i. Whenever they have a subscript like that the i would occur on the right side as well.

Answer 14

hmmm... I'm not really sure. That's what's in my lesson

Answer 15

In math there are different ways to solve a problem. They will all give the same result in the end. Which method to use depends on what has been taught to you until then and how similar problems were solved in the textbook, by the teacher, etc. So I am not sure which method you want?