(3x^3)^2(2x)^3
Here's what I've got so far
\[(3x ^{3})^{2} (2x)^{3} \] 3*2 gives me \[3x^{6} (2x) ^{3}\]
If I times 3&2 that gives me 6 Adding 6&3=9 So that gives me 6x^{9}
Rightt :)
But When I checked it to see if i was right (i subsittuted something for the x It didn't add up right
@uri Come backkkkkkk!
Great your back :D
Let me see
Did you put 6x^9?
Yep
Try putitng 6x^18
Still comes up different
@terenzreignz
What are we trying to do here?
Call in reinforcements! :P
Simplifying the original expression
Laws of Exponents
\[\LARGE (3x^3)^2(2x)^3\]
Hey how did you make that bigger? I was trying that but I couldn't make it readable!
off-topic sorry
\large \Large \LARGE \huge \Huge ^ varying degrees of size
thanks :D
anyways...
Back to the problem
<nods> Yes, the laws of exponents... Much like how multiplication distributes over addition, exponentiation distributes over multiplication. Let me show you what I mean: \[\Large (ab)^m\] You just raise all the factors to the exponent Like this \[\Large a^mb^m\]
With that in mind, you can now easily simplify this bit: \[\LARGE (3x^3)^2\color{red}{(2x)^3}\]
So that equals \LARGE 2 ^{3} * x^{3}
sorry about the formatting 2^3 *x^3
Yeah... you should enclose it in \[\Large \text{\[ <stuff>\]}\]
ah thanks
And yes, you are correct, now \[\Large 2^3 = \color{red}?\]
Hey math lesson and latex!
That would be 8
That's right. So that bit: \[\LARGE (3x^3)^2\color{red}{(2x)^3}\]just becomes \[\LARGE (3x^3)^2(\color{red}{8x^3})\] correct?
Alrighty! That makes sense
Now, do the same to this part: \[\LARGE \color{blue}{(3x^3)^2}(\color{}{8x^3})\]
OK So do I add the 3&2 first?
Consider \(\Large x^3\) as a single entity for now. Just tell me what happens to that 2-exponent.
The 2 is added after \[3x^{3}]/ is solved
No, I mean, what happens here \[\LARGE \color{blue}{(3x^3)^2}(\color{}{8x^3})\] as per this rule: \[\Large (ab)^m = a^mb^m\]
and it's \] at the end.
OH! so that means 3^3*x^3
Why does 3 get cubed? Was the exponent 3?
27^3?
And then I times 2*3
Time out
So that gives me 27^6
27^6 *8^3
Let's study this a little more closely, because your answers are (frankly) getting more and more outrageous... \[\Large (3x^3)^2\]
Err sorry about that, this is a new topic for me
Understood, but this is one of the more basic, so I really don't want you to be having a hard time with this... because your speed at your more intermediate maths depends on whether or not this stuff is just second nature to you...so...
I understand!
Okay, so let's study this closely: \[\Large (3x^3)^2\] Now, I noticed you had no difficulty whatsoever in simplifying that other one \[\Large (2x)^3=2^3x^3=8x^3 \]
Right the 3 is distributive inside the parenthesis. Now that we have a exponent inside & outside the parenthesis, which do i solve first?
I'm glad you can identify your problem :) Maybe, to get you started, we do a simple substitution.. just so you know, in a manner of speaking, where your priorities lie. Let's let \[\Large u = x^3\] so that \[\Large (3x^3)^2=(3u)^2\] okay?
OK! So I have to solve the exponint inside the parenthisis first! next to the varible the expoint is closer to!
Or, here's what I think would be the easier way to look at things... Let's look at that example you handled so well:
OK
\[\Large (2x)^3\]
Right I distributed the 3 inside the parentheses
What the exponent outside actually does is MULTIPLY ITSELF to all the exponents inside the parenthesis. Now, it's understood that when there's no exponent, that the exponent is 1...so...\[\Large (2^1x^1)^3\]
OK! So that's where the x^2 came from!
So, 3 multiplies itself to all the EXPONENTS: \[\Large 2^{1\times 3}x^{1\times3}= 2^3x^3 = 8x^3\]
Now, you can do likewise with \[\LARGE (3x^3)^2\]Only this time, not all the exponents are 1. No big deal, the same principle applies... go ahead now...
Just remember: The exponent *outside* the parentheses multiplies itself to each of the exponents *inside* the parentheses...
OK So that means \[3^{1*2} & x ^{3*2}\]
Dang it
Never mind, it seems you got the correct idea :)
So that gives me
\[\Large 3^{1\times 2}x^{3\times 2}\] simplify?
Thanks
OK so that gives me 3^2 * x^6
So that would give me 3x^8?
no... hold it
Correct up to this point: \[\Large 3^2x^6\] Now how on earth does this become \[\Large 3x^8\]??
OH! I'm adding instead of multiplying Should it become 3x^12?
No.
Hold on let me check the other equation
You don't move exponents around like that unless they have the same base!!!!
3 and x? NOT the same base.
Oh never mind
Anyway, if we went by that logic, we should get \[\Large 2^3x^3 = 2x^6 \] or something... clearly wrong
Right that's what I did
How did we simplify \[\Large 2^3x^3\]again?
We just added the two together and used the same exponint
So we got 2^3
2x^3
2^3 which is?
8
OH! OK! So 3^2 * x^6
Because 2^3 is jut a number.
And so is 3^2.
9x^6
yes. (Really, before you should even think about doing algebra, make sure your grounding in Arithmetic is solid)
So ultimately, we get \[\LARGE \color{blue}{(3x^3)^2}(\color{}{8x^3})=(\color{blue}{9x^6})(8x^3)\]
Yes I suppose I should have payed more attention in pre algebra
Thank you!
*Longest openstudy question for me to date*
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