Question

HELP!!! ∑[i=1,4,6i-1]
Is it 6i-1=6(1)-1+6(2)-1+6(3)-1+6(4)-1 ???
Not sure if this is correct
Im not getting the correct answer so I am guessing this is wrong.

Answer 1

@iGreen

Answer 2

You're right! just evaluate the sum

Answer 3

Yay someone is here @ganeshie8

Answer 4

I did but it says Im wrong

Answer 5

whats your final answer ?

Answer 6

56

Answer 7

my choices are
43
259
1295
1554

Answer 8

im getting the same
http://www.wolframalpha.com/input/?i=%5Csum%5Climits_%7Bi%3D1%7D%5E4+%286i-1%29

Answer 9

can u take a screenshot of question and attach quikc ?

Answer 10

Yes I will screen shot it and send it to my teacher. So my steps were correct?

Answer 11

I am guessing you did not paste the question correctly here

Answer 12

I sent a pic of the question

Answer 13

Is your question like this :
\[\large \sum\limits_{i=1}^4 6^{i-1}\]

or like this :
\[\large \sum\limits_{i=1}^4 6i-1\]

?

Answer 14

Wow! its a geoemetric series

Answer 15

\[\large \sum\limits_{i=1}^4 6^{i-1} = 6^{1-1} + 6^{2-1} + 6^{3-1} + 6^{4-1}\]

Answer 16

\[\large = 6^{0} + 6^{1} + 6^{2} + 6^{3}\]

Answer 17

add them ^

Answer 18

259

Answer 19

Yep!

Answer 20

you start with 6^0 because why?

Answer 21

look at previous step

Answer 22

\[\large \sum\limits_{i=1}^4 6^{\color{Red}{i}-1} = 6^{\color{Red}{1}-1} + 6^{\color{Red}{2}-1} + 6^{\color{Red}{3}-1} + 6^{\color{Red}{4}-1}\]

Answer 23

-1

Answer 24

I understand now thank you!!

Answer 25

yw:)