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I did not quite understand the solution. Case 3 isn't clear. Is it possible to elaborate the concept used here?
Sure! Let’s break down Case 3 in simpler terms.

We are given an equation of the form:

\((x^2 - 5x + 5)^{(x^2 + 8x)} = 1\)

This equation equals 1 in three situations:

  1. The base is 1: because 1^anything = 1
  2. The exponent is 0: because any non-zero number raised to the 0th power is 1
  3. The base is -1 and the exponent is even: because (-1)^even = 1

Now, focusing on Case 3: base is -1 and exponent is even

We want to find x such that the base, \(x^2 - 5x + 5\), is -1:

\(x^2 - 5x + 5 = -1\)
\((x - 2)(x - 3) = 0\)
\(x = 2 \) or \(x = 3\)

Now check whether the exponent, \(x^2 + 8x\), is even for any of these value of x:

  • x = 2 → \(x^2 + 8x = 4 + 16 = 20\) → even → valid
  • x = 3 → \(x^2 + 8x = 9 + 24 = 33\) → odd → invalid

So only x = 2 satisfies Case 3, meaning if x = 2, then the base, \(x^2 - 5x + 5\), is -1 and the exponent, \(x^2 + 8x\), is even, giving (-1)^even = 1.
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I like the solution - it’s helpful.
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I like the solution - it’s helpful.
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This is such a good question!
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