solve. logx(27)=-3/2
change to exponential form
i don't understand how to do that.
3^3=27
\[\large x^{-\frac{3}{2}} = 27\]
raise both sides by -1
to cancel the negative exponent of x
still there?
yes...trying to work it out and get a grasp on it.
i don't understand. i am getting x=1/9
remember... \[\LARGE x^{\frac{m}{n}} = \sqrt[n]{x^m}\]
still clueless...i'm just not getting it.
did you get \[\Large \frac{1}{27^{\frac{3}{2}}}\]
no
\[\large x^{-\frac{3}{2}} = 27\] \[\large (x^{-\frac{3}{2}})^{-1} = 27^{-1}\] \[\large x^{\frac{3}{2}} = \frac{1}{27}\] lol sorry i got confused...is that what you got so far?
to solve \[ x^{-\frac{3}{2}} = 27 \] use the rule \[ (x^a)^b= x^{ab} \] raise both sides to to -2/3 power (this makes the left side just x)
to make sense of \[ 27^{-2/3} \] remember: minus means flip : \( 1/27^{2/3} \) 1/3 means take the cube root 2 means square
im'm totally confused now
start with \[ x^{-\frac{3}{2}}= 27 \] raise both sides to -2/3 \[ (x^{-\frac{3}{2}})^{-\frac{2}{3}}= 27^{-\frac{2}{3}} \]
can you simplify the left side? You multiply the exponents. you get \[ x^1 = 27^{-\frac{2}{3} } \]
ok. so to solve the problem would it be x=1/9
For the right side, we can write it as \[ (27^{\frac{1}{3}})^{-2} \] Do you see how? \[ 27^{\frac{1}{3}} \] means take the cube root of 27. 27= 3*3*3 can you find the cube root?
3^3
yes 27= 3^3 and \[ (3^3)^{\frac{1}{3}} \] is ??
we find \[ 27^{\frac{1}{3}} = 3\] so now we have \[ (27^{\frac{1}{3}})^{-2} = 3^{-2} \]
1/cube root of 3
i am so much more confused now
step by step we have \[ (27^{\frac{1}{3}})^{-2} = 3^{-2} = ?? \]
1/9
Yes. x= 1/9 If you are confused, go back and try to follow the rules we used to get to the answer.
ok...i will. i have to remember this before my final. thanks so much for the step by step.
The very first step was to know how to change logx(27)=-3/2 into \[ x^{-3/2} = 27 \]
btw, it looks like you got the answer at the very beginning.
thax
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