Mathematics
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OpenStudy (anonymous):
how do I simplify (27x^(1/2)y^(6))^(-1/3)
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OpenStudy (jdoe0001):
any part you need clearing out?
OpenStudy (anonymous):
my answer is 1/3x^(1/6) y^2
OpenStudy (anonymous):
but I need to show my steps and i don't know how
OpenStudy (anonymous):
hello?
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OpenStudy (jdoe0001):
$$
\pmatrix{27x^{\frac{1}{2}}y^6}^{-\frac{1}{3}}
$$
OpenStudy (jdoe0001):
start by the outtermost exponent, what would that give you?
OpenStudy (anonymous):
yup thats right
OpenStudy (anonymous):
-1/3?
OpenStudy (anonymous):
(27x^(1/2)y^(6))^(-1/3) can you rewrite it like shown on our paper use the equation botton
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OpenStudy (jdoe0001):
yes, but what would say... \(a^{-1} = ? \)
OpenStudy (anonymous):
-a?
OpenStudy (anonymous):
ahh I am so confused
OpenStudy (anonymous):
yeah
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OpenStudy (jdoe0001):
because if you dunno the "exponent rules", then there's no use for this test
OpenStudy (anonymous):
ok so do I just apply each individual part to the rules?
OpenStudy (jdoe0001):
yes, starting from the outtermost exponent
OpenStudy (anonymous):
o
OpenStudy (jdoe0001):
so, from the sheet there in the link, look at the \(a^{-m} \)
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OpenStudy (anonymous):
it'd be the -1/3
OpenStudy (jdoe0001):
in your case, yes
OpenStudy (jdoe0001):
so, what would that leave you with?
OpenStudy (anonymous):
3
OpenStudy (jdoe0001):
$$
a^{-\color{red}{2}} = \frac{1}{a^\color{red}{2}}\\
so\\
\pmatrix{27x^{\frac{1}{2}}y^6}^{-\color{red}{\frac{1}{3}}} \implies ?
$$
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OpenStudy (anonymous):
\[27x ^{1/2}y ^{6}/ (1/3)\]
OpenStudy (anonymous):
right?
OpenStudy (jdoe0001):
sorry I got a bit lagged
OpenStudy (jdoe0001):
well, I'll put this way
$$
a^{-\color{red}{2}} = \frac{1}{a^\color{red}{2}}\\
so\\
\pmatrix{a}^{-\color{red}{\frac{1}{3}}} \implies ?
$$
OpenStudy (anonymous):
\[1/(27x ^{1/2}y^6)^{-1/3}\]
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OpenStudy (anonymous):
right?
OpenStudy (jdoe0001):
well, very close, yes, it becomes a fraction, but the "negative exponent" once at the denominator becomes "positive"
OpenStudy (anonymous):
oh whoops I forgot
OpenStudy (jdoe0001):
$$
a^{-\color{red}{2}} = \frac{1}{a^\color{red}{2}}\\
so\\
\pmatrix{27x^{\frac{1}{2}}y^6}^{-\color{red}{\frac{1}{3}}} \implies
\cfrac{1}{\pmatrix{27x^{\frac{1}{2}}y^6}^{\color{red}{\frac{1}{3}}}}
$$
OpenStudy (anonymous):
\[1/(27^{1/2}y ^{6})^{1/3}\]
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OpenStudy (jdoe0001):
as far as having an exponent outside a parentheses, see the rules sheet that shows
\(\large (a^m)^n = a^{mn}\)
OpenStudy (anonymous):
so it comes into parenthesis
OpenStudy (anonymous):
I would multiply it in but by which one?
OpenStudy (jdoe0001):
yes
OpenStudy (jdoe0001):
well -> \(\large (a^2b^3c)^4 = (a^{2\times4} b^{3\times 4} c^{1\times 4}) \)
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OpenStudy (anonymous):
oh so all of them
OpenStudy (anonymous):
6*1/3 is 2 and 6* 1/2 is 3
OpenStudy (anonymous):
so my new equation would look like \[1/27x^3 y^2\]
OpenStudy (anonymous):
is that right?
OpenStudy (anonymous):
oh wait I found an error
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OpenStudy (jdoe0001):
ahem, you're multiplying by a fraction, \(\frac{1}{3}\) not by "3"
OpenStudy (anonymous):
it'd be 1/3 * 1/2 which =1/6 and 1/3*6=2
OpenStudy (jdoe0001):
yes
OpenStudy (anonymous):
yeah so my new equation would be 1/27x^(1/6) y^2
OpenStudy (anonymous):
is that right?
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OpenStudy (jdoe0001):
well, yes, just that, any number by itself, usually would have an exponent of 1, so
25 = 25^1
27 = 27^1
\(\large 27^{1\times \frac{1}{3}}\)
OpenStudy (anonymous):
ok now what?
OpenStudy (jdoe0001):
$$\huge {
\pmatrix{27x^{\frac{1}{2}}y^6}^{-\color{red}{\frac{1}{3}}} \implies
\cfrac{1}{\pmatrix{27x^{\frac{1}{2}}y^6}^{\color{red}{\frac{1}{3}}}}\\
\implies \cfrac{1}{27^{\color{red}{\frac{1}{3}}}x^{\color{red}{\frac{1}{6}}}y^\color{red}{2}}
\implies \cfrac{1}{\sqrt[\color{red}{3}]{27}\sqrt[\color{red}{6}]{x}y^\color{red}{2}}
}
$$
OpenStudy (anonymous):
ok and then I get
OpenStudy (anonymous):
1/3x^(1/6)y^2
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OpenStudy (anonymous):
right?
OpenStudy (jdoe0001):
yes
OpenStudy (anonymous):
yay
OpenStudy (anonymous):
thank you!
OpenStudy (jdoe0001):
yw
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OpenStudy (anonymous):
can you help me with another problem?
OpenStudy (jdoe0001):
if I can
OpenStudy (anonymous):
ok it looks like \[-5/\sqrt{5}-\sqrt{3}\]
OpenStudy (jdoe0001):
right, a fractional exponent, just means a root, so
$$\large {
a^{\frac{n}{m}} = \sqrt[m]{a^n}
}
$$
OpenStudy (jdoe0001):
is that => $$\large {
\cfrac{-5}{\sqrt{5}-\sqrt{3}}
}?
$$