Question

find a general formula for the nth term

Answer 1

geometric series

Answer 2

\(n^{th}\) term of what?

Answer 3

a9=1/7 and r=1/7

Answer 4

If \(a, ar, ar^2, ar^3 \cdots \cdots \)

Answer 5

\(ar^{n-1}\) is the \(n^{th}\) term.

Answer 6

yes to start with what we are given here:
\[a_9 = \frac{1}{7} \\ a r^{9-1} = \frac{1}{7}\]

Answer 7

This step you are getting?

Answer 8

the answers are

an=7^7*(1/7)^n-1
an=7^6*(1/7)^n-1
an=7^9*(1/7)^n-1
an=7^8*(1/7)^n-1

Answer 9

Don't bother for the answers. :)

Answer 10

yes

Answer 11

\[ar^8 = \frac{1}{7}\]

Answer 12

ok

Answer 13

r is also given to you so put its value:
\[a(\frac{1}{7})^8 = \frac{1}{7}\]

Answer 14

\[(\frac{m}{n})^a = \frac{m^a}{n^a}\]

Answer 15

Using the above :
\[a (\frac{1^8}{7^8}) = \frac{1}{7}\]

Answer 16

\(1^8 = 1\) only.

Answer 17

\[a( \frac{1}{7^8}) =\frac{1}{7}\]

Answer 18

Alright up to here?

Answer 19

yeah

Answer 20

Let us multiply both the sides by : \(7^8\):

\[a = \frac{7^8}{7}\]

Answer 21

Good??

Answer 22

yes

Answer 23

can you tell what could be my next step?? can you reduce that more??

Answer 24

dividing?

Answer 25

use rule of exponents:
\[\frac{x^m}{x^n} = x^{m-n}\]

Answer 26

So tell me:
\[\frac{7^8}{7^1} = ??\]

Answer 27

we are not writing a Novel here, write in using few words. :P

Answer 28

823543

Answer 29

@waterineyes

Answer 30

Oh dear, just write that in powers, you need to calculate that.. Check your options, they are given using powers only..

Answer 31

\[\frac{7^8}{7} = 7^7\]

Answer 32

oh

Answer 33

Is it right?

Answer 34

*you need not to calculate that..

Answer 35

let me check

Answer 36

yes

Answer 37

What you checked?

Answer 38

:P

Answer 39

so its 7^7*1/7^n-1

Answer 40

yeah, you can tell the answer with \(a\) only.

Answer 41

exponent = 7 is in only first option, so all okay?

Answer 42

Any doubt, anywhere?

Answer 43

yep thanks :)

Answer 44

and no lol

Answer 45

you are welcome dear. :)

Answer 46

i have 1 more its kind of the same

Answer 47

a5=1/8 and r= 1/2

Answer 48

@waterineyes

Answer 49

can you try first?

Answer 50

Just do it, I will alert you if you commit mistake anywhere :) Go ahead..