Factorize the following expressions : `x^4+4x^2+3`

Explanation

To factorize the expression \( x^4 + 4x^2 + 3 \), we can follow these steps:

### Step 1: Substitute
Let \( y = x^2 \). This transforms the expression into \( y^2 + 4y + 3 \).

### Step 2: Factor the Quadratic
Now we need to factor the quadratic expression \( y^2 + 4y + 3 \). We look for two numbers that multiply to \( 3 \) (the constant term) and add up to \( 4 \) (the coefficient of \( y \)). The numbers \( 1 \) and \( 3 \) satisfy these conditions.

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