Factor the high-degree polynomial 2x^5-4x^3+2x to solve the polynomial equation 2x^5-4x^3+2x to solve the polynomial equation 2x^5-4x^3+2x=0

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To factor the polynomial \( 2x^5 - 4x^3 + 2x \), we can start by factoring out the greatest common factor from all the terms.

The greatest common factor here is \( 2x \). So we factor \( 2x \) out:

\[ 2x^5 - 4x^3 + 2x = 2x(x^4 - 2x^2 + 1) \]

Now, we need to factor the remaining polynomial \( x^4 - 2x^2 + 1 \). We can recognize that \( x^4 - 2x^2 + 1 \) is a quadratic in terms of \( x^2 \). Let's make a substitution where \( u = x^2 \):

\[ u^2 - 2u + 1 \]

This can be factored as:

\[ (u - 1)^2 = (x^2 - 1)^2 \]

Now substituting back \( u = x^2 \):

\[ x^4 - 2x^2 + 1 = (x^2 - 1)^2 \]

The expression \( x^2 - 1 \) can be factored further using the difference of squares:

\[ x^2 - 1 = (x - 1)(x + 1) \]

Thus, we have:

\[ (x^2 - 1)^2 = ((x - 1)(x + 1))^2 = (x - 1)^2(x + 1)^2 \]

Putting everything together, we can rewrite the original polynomial as:

\[ 2x^5 - 4x^3 + 2x = 2x((x - 1)^2(x + 1)^2) \]

Setting this equal to zero to solve the polynomial equation \( 2x^5 - 4x^3 + 2x = 0 \):

\[ 2x((x - 1)^2(x + 1)^2) = 0 \]

This equation is satisfied if any of the factors equal zero:

  1. \( 2x = 0 \) implies \( x = 0 \)
  2. \( (x - 1)^2 = 0 \) implies \( x = 1 \) (with a multiplicity of 2)
  3. \( (x + 1)^2 = 0 \) implies \( x = -1 \) (with a multiplicity of 2)

Thus, the solutions to the equation \( 2x^5 - 4x^3 + 2x = 0 \) are:

\[ x = 0, \quad x = 1 \quad \text{(multiplicity 2)}, \quad x = -1 \quad \text{(multiplicity 2)} \]