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What is the solution for this inequality? 8x⁵-32 A. X=-4 B. X=4 c. X²-4 D x = 4

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Final Answer:

The solution for this inequality is:

B. X = 4

Step-by-step explanation:

The given inequality is
\(8x^5 - 32 < 0\). To find the solution, we can first factor out the common factor of 8:


\[8(x^5 - 4) < 0\]

Now, we set each factor equal to zero to find critical points:


\[x^5 - 4 = 0\]

Solving for
\(x\), we get \(x = 4\). This critical point divides the real number line into two intervals:
\((-\infty, 4)\) and \((4, \infty)\).

To determine the sign of
\(8(x^5 - 4)\) in each interval, we choose test points. Taking a test point from the interval
\((-\infty, 4)\), say \(x = 0\), we substitute it into the inequality:


\[8(0^5 - 4) < 0\]

This simplifies to
\(8(-4) < 0\), which is true. Therefore, the solution lies in the interval
\((-\infty, 4)\).

Now, taking a test point from the interval
\((4, \infty)\), say \(x = 5\), we substitute it into the inequality:


\[8(5^5 - 4) < 0\]

This simplifies to
\(8(311) > 0\), which is false. Therefore, the solution does not lie in the interval
\((4, \infty)\).

Combining both intervals, the solution to
\(8x^5 - 32 < 0\) is \(x \in (-\infty, 4)\), and the correct answer is
\(B. X = 4\).

User Matt Mc
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