describe how to transform (^3 sqrt x^4)^5 into an expression with a rational exponent. make sure you respond with complete sentences
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\[\left( \sqrt[3]{X ^{4}} \right)^{5}\]
this is the equation please help
Which part confuses you?
i wouldn't know how to transform it into an expression with a rational exponent.
first, do you know how to write \[\sqrt[3]{x} or \sqrt{x} \] as an exponent?
First, if you have something like: \[y = \sqrt[3]{x}\] that means that: \[y^{3} = x\] Are you with me so far?
yes so far i was kind of behind with my class so anything helps please
Also, do you know how to simplify an expression like this: \[(x^{3})^{4}\]
nope please explain
what about: \[x^{3}*x^{3}\] Do you know what this equals?
yes \[X^{3}\]
?
Not quite...
Here's an example: What's 8*8?
64
Because \[8 = 2^{3}\] And 8*8 is the same as: \[2^{3}*2^{3}\]
So I'll give you a second shot: \[x^3*x^3 = ?\]
\[X^{6}\]
Bingo!
took me a min little slow
Another way of saying that is that: \[x^a*x^b = x^{a+b}\]
oh okay
And, with exponents, \[(x^a)^3 = x^a*x^a*x^a = x^{a+a+a} = x^{3a}\]
So, \[x^a*x^b = x^{a+b}\] BUT, \[(x^a)^b = x^{ab}\]
Are you getting a hang of this?
now that your taking your time to explain it I'm starting to understand it
Ok, great!
Now, the hardest part about that first expression you gave me was the "cubed root". You have any idea how to deal with those??
nope
First, I want you to simplify these two expressions while I type something about cubed roots: \[x^3*2x^2\] and \[(x^4)^7\]
\[2x^{5}\]
First, lets say I give you something like: \[(x^a)^3\] a.) first, simplify this b.) if I say that: \[(x^a)^3= x\] what do you think "a" equals.
\[\left(x ^{47} \right)\]
a equals 4
Whoops, not quite. You got the first question right (I even threw in that extra "2" to trip you up).
Look back at that second question -- (x^4)^7
\[\left( X^{27} \right)\]
You're almost there, except remember: the exponent equals 4*7,
i mean 28 sorry
Ok, great!
Here's another one: If \[x^a = x\] Then what is "a" equal to?
\[x^{2}\]
So you're saying: \[x^2 = x\] ?
i believe so.
Now, that IS true when x = 0 or when x =1.... but what about for ALL x's
Well, try plugging in a number for "x" to see. For instance, try out "x=3"
will it be 9?
You're right: 3^2 = 9. Now, let's go back to that original question: \[x^a = x\] If "a" was equal to "2" then that would mean that: \[x^2 = x\] And, if we plugged in "3" for "x" then you would have: \[3^2 = 3\] But you just said that 3^2 = 9 (which is true). Therefore, \[3^2 \neq 3\]
This might sound boring but I swear this part is important for when you turn the "cubed root" into an exponent...
sorry was in restroom
Next time you can just say "I was busy". :)
sorry but thank you
I'll give you a second to catch up -- I have to take some medicine myself (I'm sick).
okay thank you and sorry to hear that i just got over a cold myself.
Ok, now back to that question I gave you earlier: \[x^a = x\]
\[x^{a2}\]
Not quite. But the good news is that it's easier than it looks.
a = 1 Because \[x^1 \] is just another way of writing "x"
ohh yea duh i should of got that right
Because if: \[x^3 = x*x*x\] \[x^2 = x*x\] Then \[x^1 = x\]
Now, back to roots, what is: \[\sqrt[3]{x}*\sqrt[3]{x}*\sqrt[3]{x}\]
\[\sqrt[27]{x}\]
\[\sqrt[27]{X}^{3}\]
How about this one: \[\sqrt{x}*\sqrt{x}\]
Hint: It's easier than it looks...
And it always helps if you plug in some numbers: \[\sqrt{16}*\sqrt{16} = ?\]
but how do you always know which numbers to plug in?
No, whenever you see an "x" that means that it could stand for ANY number. Thus, I can choose any number I want just to test my answers. There's nothing special about the "16" I chose--I chose it because the square root of 16 is easy to calculate (it's just "4"). Similarly, when talking about cube roots, I would probably chose an a number like "27" because I know from the top of my head that the cube root of 27 equals 3.
Now, if I gave you something like: \[9 = \sqrt{x}\] You can't just plug in any number you want for "x" --you have to SOLVE for x. But, if you just have regular expression (i.e. with no "equals" sign) then you can always plug in a number for "x" and see if your solution makes sense.
Remember how I earlier wrote that: \[y = \sqrt[3]{x}\] means that: \[y ^{3} = x\]? Well, that means that: \[\sqrt[3]{y^3} = x\]
yes
Actually, sometimes it's most helpful to work backwards. Because it will all make sense after I give you the answer... First, to rewrite a cubed root as an exponent: \[\sqrt[3]{x} = x^{\frac{ 1 }{ 3 }}\]
and, because: \[(x^a)^b = x^{a*b}\] That means that you can take any type of root such as: \[\sqrt[7]{x^5}\] and rewrite it as: \[(x^5)^\frac{ 1 }{ 7 }\] which than can be simplified to: \[x^\frac{ 5 }{ 7 }\]
So to go back to your original question: \[(\sqrt[3]{x^4})^5 = ((x^4)^\frac{ 1 }{ 3 })^5 = (x^\frac{ 4 }{ 3 })^5 = x^\frac{ 20 }{ 3 }\] Thus your answer is "x raised to the twenty thirds power" or similarly, "x to the 6 and two thirds power"
i truly thank you so much you are the biggest help I've ever had truly better than my own teachers but then again I'm in online so i guess I'm my own teacher and i suck lol
Well, exponents can be confusing... Good luck with the rest of your work!
thanks
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