MHB Solving Cubic Root Algebra: Don't Know the Steps

AI Thread Summary
The discussion centers around confusion regarding the steps to solve a cubic root algebra problem. The main point of contention is the assertion that "a is not supposed to be -1," which is highlighted as a critical rule in the equation. Participants express uncertainty about the validity of the equation leading to the answer shown in a referenced image. One user suggests that a typo may exist, particularly questioning the expression involving the cubic root of 0.125. Overall, clarity on the steps and correctness of the equation is sought.
STS
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I don't understand this.
a is not suppose to be -1; this is the only rule in the equation
The answer is the second picture, I just don't know the steps that lead to that answer.
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STS said:
I don't understand this.
a is not suppose to be -1; this is the only rule in the equation
The answer is the second picture, I just don't know the steps that lead to that answer.
In order for this to be correct we would need [math]\sqrt[3]{ 0.125 - 0.5 } = 0[/math], which clearly isn't true. Is there a typo?

-Dan
 
Hi STS.

You probably mean the following expression:
$$\frac{4a^2-10\times\sqrt[3]{0.064}}{3a+3+{\color{red}\sqrt[3]{0.125}}-0.5}.$$
 
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