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For what value of x, the following expre...

For what value of x, the following expressions are positive ?
`3x^(2)+4x+4`

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To determine for what values of \( x \) the expression \( 3x^2 + 4x + 4 \) is positive, we can follow these steps: ### Step 1: Identify the coefficients We start with the quadratic expression: \[ f(x) = 3x^2 + 4x + 4 \] Here, we identify the coefficients: - \( a = 3 \) - \( b = 4 \) - \( c = 4 \) ### Step 2: Calculate the discriminant The discriminant \( \Delta \) of a quadratic equation \( ax^2 + bx + c \) is given by: \[ \Delta = b^2 - 4ac \] Substituting the values of \( a \), \( b \), and \( c \): \[ \Delta = 4^2 - 4 \cdot 3 \cdot 4 \] Calculating this gives: \[ \Delta = 16 - 48 = -32 \] ### Step 3: Analyze the discriminant Since the discriminant \( \Delta \) is less than 0 (\( \Delta < 0 \)), this indicates that the quadratic equation does not have real roots. Therefore, the expression \( f(x) \) does not cross the x-axis. ### Step 4: Determine the sign of the quadratic expression Since \( a = 3 \) (the coefficient of \( x^2 \)) is positive, the parabola opens upwards. Given that there are no real roots and the parabola opens upwards, the expression \( f(x) = 3x^2 + 4x + 4 \) is positive for all real values of \( x \). ### Conclusion Thus, the expression \( 3x^2 + 4x + 4 \) is positive for all \( x \in \mathbb{R} \). ---
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