Question

Simplify 3^-9 / 3^-12

Answer 1

answers: 3^3

3^21

1/3^21

1/3^3

Answer 2

do you know the rule:\[x^a/x^b=x^{a-b}\]

Answer 3

nope sure dont

Answer 4

what have you been taught about indexes?

Answer 5

nothing at all that i can recall

Answer 6

no pun intended

Answer 7

so how do they expect you to solve this?
have you been told to use any specific method?

Answer 8

i think we have i just dont remember

Answer 9

well at the very least you need to know the rules of index multiplication and division.

Answer 10

prolly do just dont remember what they are

Answer 11

e.g. the rule I just showed you can be proved with following example:\[\frac{x^5}{x^3}=\frac{x*x*x*x*x}{x*x*x}=x*x=x^2\]

Answer 12

oooo thtz right i remember now thx

Answer 13

so in your case,\[3^{-9}/3^{-12}=3^{-9-(-12)}=3^{-9+12}=3^3\]

Answer 14

yup i got it thanks alot

Answer 15

yw