Anthonyk2013
Junior Member
- Joined
- Sep 15, 2013
- Messages
- 132
8-1/4t^3=0
8-1/4t^3=0
I know this incorrect but not sure what to do.
-1/4t3 =8
-1/4=8t3
-1/32=t3
So your expression is:
\(\displaystyle - \dfrac{1}{4t^3} \ = 8\)
\(\displaystyle t^3 = - \dfrac{1}{32} = - 2^{-5}\)
\(\displaystyle \displaystyle{t = -2^{\left [-\frac{5}{3}\right ]}}\)
Yes up until \(\displaystyle = - 2^{-5}\) Don't understand this part where -5 came from
\(\displaystyle = - 2^{-5}\)
\(\displaystyle \displaystyle{t = -2^{\left [-\frac{5}{3}\right ]}}\)
I'm assuming you're still confused about where the 2^(-5) came from. Think about what negative exponents mean. n^(-1) can be rewritten as 1/n, so what does n^(-2) mean? Apply that same logic to 2^(-5). Once you have your new way of writing it, do you see that term in your original equation? Then when you get to t^3 = 2^(-5), you can simplify by taking the cube root of both sides. Like so:
\(\displaystyle t=\sqrt[3]{2^{-5}}\)
And since n^(1/3) means the same thing as the cube root of n, do you see why you can rewrite that as t = 2^(-5/3)?