Estuardo_needs_
Mar 3, 2009, 03:41 PM
X to the 4/3 power minus 5 equals 11
Perito
Mar 3, 2009, 04:01 PM
X^4/3 - 5 = 11
X^(4/3) = 16
Take the logarithm of both sides and simplify. Once you get it into the form
Log(x) = something
Take the antilog (10 to the power) and you have your answer.
You can also use the natural log instead of the common log, if you wish.
Hint: Answer is between 1 and 20
ebaines
Mar 4, 2009, 07:26 AM
Much easier approach:
x^{4/3} = 16 \\
Cube both sides:
(x^{4/3})^3 = 16^3 \\
Recall that ({x^a})^b = x^{ab}, hence
(x^{4/3})^3 = x^4
So you have:
x^4 = 16^3
Can you take it from here?