Rewrite without rational exponents, and simplify, if possible. 49^3/2
with a rational exponent, the numerator is the power and the denominator is the root
making this \[\sqrt{49^3}\] take the square root first, cube second
so i guess it would be easier if you write \(\sqrt{49}^3\)
where did the 2 go? I'm sorry i suck at radical problems!
the two in the denominator means take the "square root"
notice that the problem says exactly "Rewrite without rational exponents" when you get rid of the rational exponent, the 2 in the denominator becomes the square root sign
so since 7 times 7 is 49 would i then do 49^3?
you could write \[49^{\frac{3}{2}}=\sqrt[2]{49^3}\] but no one writes an "index" of two
or 7^3
ahhh ok
the second one
as you said, \(7\times 7=49\) which means \(\sqrt{49}=7\)
so 343 is the answer?
therefore \[\sqrt{49}^3=7^3=343\] yes you are right
ahhh ok, that makes sense! thank you!
yw you got more or is that it?
I have a lot more problems with radicals!!!! One of my other questions says Rewrite with positive exponents, and simplify if possible? would i do the same thing one of the problems is 27^-1/3
this one is a little different because of the minus sign in the exponent
\[\large 27^{\frac{1}{3}}=\sqrt[3]{27}\] see this time you write the index because of the cubed root do you know what the cubed root of 27 is?
3
got it
now the minus sign in the exponent does not mean make it negative, it means take the reciprocal, in other words, flip it do you know what the reciprocal of 3 is ( don't think too hard)
-3?
or 1/3
nah you fell for it don't make it negative take the reciprocal
second one
so \[\large 27^{-\frac{1}{3}}=\frac{1}{\sqrt[3]{27}}=\frac{1}{3}\]is the right answer
still need help?
that one makes sense, can you help me with a different question?
yes of course
thanks, another questions says use the laws of exponents to simplify. Write the answers with positive exponents. 5^3/4 * 51/8
i take it this is \[\large 5^{\frac{3}{4}}\times 5^{\frac{1}{8}}\] right?
your job here is only to add \(\frac{3}{4}+\frac{1}{8}\) to get the exponent
yes, and 7/8
you are right since \[\frac{3}{4}+\frac{1}{8}=\frac{6}{8}+\frac{1}{8}=\frac{7}{8}\] your answer is \[\large 5^{\frac{7}{8}}\]
thats it? thats easy!
yeah adding exponents is pretty easy if you can add some people get stuck at adding fractions any more?
haha yah! if thats ok?
yeah sure
it says use rational exponents to simplify. write the answer in radical notation if appropriate. \[(\sqrt[3]{ab})\]^15
sorry the ^15 is supposed to be right next to the equation
\[\large\left(\sqrt[3]{ab}\right)^{15}\] right?
yup
you are going to be amazed (maybe) at how easy this one is how many times does 3 go in to 15?
5 times
ok so the answer is \(\left(ab\right)^5\)
wow that is easy! thanks
don't forget you can go backwards too \[\sqrt[3]{x}=x^{\frac{1}{3}}\] so \[\large \sqrt[3]{x}^{15}=x^{\frac{15}{3}}=x^5\]
yeah and at the beginning you said you sucked at radicals if i recall...
any more of these?
haha yah, i just get confused by the different questions i guess!
nd yah, but i have to go back and apply this to some other questions first, so im good for a little bit! thanks!!
yw good luck, hope this helped
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