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Задача Задача №2617781
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12 января 2025 15:43 · публичный вопрос
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8^(2/х)-2^((2х+3)/х)-32=0

Ответ нейросети
12 января 2025 15:43

To solve the equation \( 8^{\frac{2}{x}} - 2^{\frac{2x + 3}{x}} - 32 = 0 \), we can start by expressing all terms with the same base.

We know that \( 8 = 2^3 \), so we can rewrite the first term:

\[ 8^{\frac{2}{x}} = (2^3)^{\frac{2}{x}} = 2^{\frac{6}{x}} \]

Now let's look at the second term \( 2^{\frac{2x + 3}{x}} \):

\[ 2^{\frac{2x + 3}{x}} = 2^{2 + \frac{3}{x}} \]

Substituting back into the original equation gives:

\[ 2^{\frac{6}{x}} - 2^{2 + \frac{3}{x}} - 32 = 0 \]

Next, we can express \( 32 \) as a power of \( 2 \):

\[ 32 = 2^5 \]

Now we rewrite the equation:

\[ 2^{\frac{6}{x}} - 2^{2 + \frac{3}{x}} - 2^5 = 0 \]

To simplify the equation, let's set \( y = 2^{\frac{3}{x}} \). Then we have:

\[ 2^{\frac{6}{x}} = (2^{\frac{3}{x}})^2 = y^2 \] and \[ 2^{2 + \frac{3}{x}} = 2^2 \cdot 2^{\frac{3}{x}} = 4y \]

Now substituting these back into the equation results in:

\[ y^2 - 4y - 32 = 0 \]

This is a quadratic equation and can be solved using the quadratic formula:

\[ y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \] where \( a = 1, b = -4, c = -32 \).

Calculating the discriminant:

\[ b^2 - 4ac = (-4)^2 - 4(1)(-32) = 16 + 128 = 144 \]

Now we can find \( y \):

\[ y = \frac{4 \pm \sqrt{144}}{2} \] \[ y = \frac{4 \pm 12}{2} \]

This gives us two potential solutions for \( y \):

  1. \( y = \frac{16}{2} = 8 \)
  2. \( y = \frac{-8}{2} = -4 \) (not possible since \( y \) must be positive)

Since \( y = 2^{\frac{3}{x}} \), set \( y = 8 \):

\[ 2^{\frac{3}{x}} = 8 \implies 2^{\frac{3}{x}} = 2^3 \]

Thus, we have:

\[ \frac{3}{x} = 3 \implies x = 1 \]

Therefore, the solution to the equation is:

\[ \boxed{1} \]