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E^y = (4x-x^3)/(x+2) rearrange to find x in terms of y

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The solutions for x in terms of y are x = 2, x = -2, and
x = -e^y.

To solve the equation
\(e^y = (4x - x^3)/(x + 2)\) for x in terms of y, follow these steps:

Step 1: Clear the Fraction:

Multiply both sides of the equation by x + 2 to clear the fraction:


\[ e^y(x + 2) = 4x - x^3 \]

Step 2: Rearrange the Equation:

Expand the left side and move all terms to one side of the equation:


\[ e^yx + 2e^y = 4x - x^3 \]

Rearrange to get all terms on one side:


\[ x^3 + e^yx - 4x + 2e^y = 0 \]

Step 3: Factor the Equation:

Factor out common terms:


\[ (x - 2)(x + 2)(x + e^y) = 0 \]

Step 4: Solve for x:

Set each factor equal to zero and solve for x:


x - 2 & = 0 \implies x = 2


x + 2 & = 0 \implies x = -2


x + e^y & = 0 \implies x = -e^y

So, the solutions for x in terms of y are x = 2, x = -2, and
x = -e^y.

User Alhpa Delta
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