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don't think im retarded i spent a half a year in Pre-Calc and a full year in Calc. This stuff is basic algebra and you don't know how much it shames me for being confused but in my defense i always hated math.

So my brothers doing his math HW and he ask me for help heres the problem.


(X^-2)^-2
-------------
X^5

i said the answer was X^4/X^5

his friend said the answer was 1/X^9

i talked to said friend over the phone and he sounded very convincing while i was kinda like >>

Now heres the next problem

(2x^-3)^-2

i said the answer was 2x^6

his friend said the answer was 2/X^6

Im completely confused and lack all confidence in my math abilities at this point but i feel bad for not being able to help especially when i should know this stuff. So who is right here im right don't explain it if im wrong pls tell me why. And plz ppl im letting down my guard here don't lol @ me to much

((X^-2)^-2 )/X^5 = 1/x = X^4/X^5

(2x^-3)^-2 = 1/4x^6

^

for this one is it (2x^-3)^-2 or ((2x)^-3)^-2


if it is ((2x)^-3)^-2 = 64x^6= (2x)^6

thats my answer i am not exactly sure if it is right

as I've said before; when in doubt answer is 7.5

I'm going to pass my geometry test like that tommorow now

thanks

you can't tell when im joking?

Never mind for number 2 it's X^6/4

If your dealing with negative exponents, then you must take the reciprocal of it, meaning move it to the bottom, and then you should knwo the rest, its basic fractions.

No, when in doubt, x=3, and y=2.

are you sure about this?

i am pretty sure i am right

Final answer...

1/X

(X^6)/4

Yeah, you can test it by setting x as any number and seeing if they equal.

say (2X^3)^2



by some of your logic i would square everything int he parenthesis so the answer would be 4X^6

You are, as far as I can see.

EDIT:
Ell is right on #2

(x^6)/4

Laws of exponents, yes you would do that.

im getting conflicting answers....

i trust Aiyas and Ell but Aiyas trust crazy whose answer is different from Ell's

Those two equations are different.

*explodes* how did i make it through HS....*cries* i took AP calc....i got a 2 thats not good but it means i at least got my name and 1 problem right

Let me clarify:

#1 1/x

#2 (x^6)/4

Yay

how do you figure? can you explain in words...

read the whole thing

/sigh, here's where you went wrong

(2x^-3)^-2

1/(2x^-3)^2

you did: 1/(2^2*x^3(2)) rather than 1/(2^2x^-3(2))

for 1

x^4/X^5 which is what u got = xxxx/xxxxx

the four x cancel out leave 1 x on bottom = 1/x

I give up ..... my brother and his math thx for all your help but i can honestly say im more confused now. but i know you guys actually took me serious and i really appreciate that (you don't know how much)

feel free to continue though if it'll bug you but im going back to do my safe chemistry work...where laws and rules are in english and everything makes sense...

i had 2 answer for number 2 u can either consider:
2x as a whole
or
2 and x as separate

Anything to a negative power is just the reciprocal. So x^-1 equals 1/x^1, x^-2 equals 1/x^2, x^-3 equals 1/x^3 ect ect.

For problem one, (x^-2)^-2 is just (1/x^2)^-2 which is 1/((1/x^2)^2) and that equals 1/(1/x^4) which equals x^4. Divide that by x^5 and you get 1/x since the x's cancel.

Same thing for problem two. 2x^-3 equals 2/x^3. And (2/x^3)^-2 is 1/((2/x^3)^2) which is 1/(4/x^6) and that equals x^6/4.

Edit: The chemistry class I had was basically half math, so it was like taking one and a half math classes a day

#1

(x^-2)^-2 / x^5

Multiply exponents in the numerator. (-2 * -2 = 4)

You should now have:

(x^4)/(x^5)

which is equivalent to:

x^(4-5) = x^-1 = 1/x

#2

(2x^-3)^-2

Rewrite as 1/(2x^-3)^2

Multiply the square to get 1/(4x^-6), or (1/4)*(1/(x^-6))

The second factor can be re-written as (x^-6)^-1, or x^(-6*-1), or x^6

So you have (1/4)*x^6, or x^6/4

I'm pointing out that the 2 and x^-3 are separate one is done wrong.