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Determine the nature of roots of the fol...

Determine the nature of roots of the following quadratic equations:
(i) `2x^(2)+5x-4=0` (ii) `9x^(2)-6x+1=0`
(iii) `3x^(2)+4x+2=0` (iv) `x^(2)+2sqrt2x+1=0`
(v) `x^(2)+x+1=0` (vi) `x^(2)+ax-4=0`
(vii) `3x^(2)+7x+(1)/(2)=0`
(viii) `3x^(2)-4sqrt3x+4=0`
(ix) `2sqrt3x^(2)-5x+sqrt3=0` (x) `(x-2a)(x-2b)=4ab`

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To determine the nature of the roots of the given quadratic equations, we will calculate the discriminant (D) for each equation. The discriminant is given by the formula: \[ D = b^2 - 4ac \] Where \( a \), \( b \), and \( c \) are the coefficients of the quadratic equation \( ax^2 + bx + c = 0 \). ### Step-by-Step Solutions: 1. **Equation (i):** \( 2x^2 + 5x - 4 = 0 \) - Coefficients: \( a = 2 \), \( b = 5 \), \( c = -4 \) - Discriminant: \[ D = 5^2 - 4 \cdot 2 \cdot (-4) = 25 + 32 = 57 \] - Since \( D > 0 \), the roots are **real and distinct**. 2. **Equation (ii):** \( 9x^2 - 6x + 1 = 0 \) - Coefficients: \( a = 9 \), \( b = -6 \), \( c = 1 \) - Discriminant: \[ D = (-6)^2 - 4 \cdot 9 \cdot 1 = 36 - 36 = 0 \] - Since \( D = 0 \), the roots are **real and equal**. 3. **Equation (iii):** \( 3x^2 + 4x + 2 = 0 \) - Coefficients: \( a = 3 \), \( b = 4 \), \( c = 2 \) - Discriminant: \[ D = 4^2 - 4 \cdot 3 \cdot 2 = 16 - 24 = -8 \] - Since \( D < 0 \), the roots are **complex** (no real roots). 4. **Equation (iv):** \( x^2 + 2\sqrt{2}x + 1 = 0 \) - Coefficients: \( a = 1 \), \( b = 2\sqrt{2} \), \( c = 1 \) - Discriminant: \[ D = (2\sqrt{2})^2 - 4 \cdot 1 \cdot 1 = 8 - 4 = 4 \] - Since \( D > 0 \), the roots are **real and distinct**. 5. **Equation (v):** \( x^2 + x + 1 = 0 \) - Coefficients: \( a = 1 \), \( b = 1 \), \( c = 1 \) - Discriminant: \[ D = 1^2 - 4 \cdot 1 \cdot 1 = 1 - 4 = -3 \] - Since \( D < 0 \), the roots are **complex** (no real roots). 6. **Equation (vi):** \( x^2 + ax - 4 = 0 \) - Coefficients: \( a = 1 \), \( b = a \), \( c = -4 \) - Discriminant: \[ D = a^2 - 4 \cdot 1 \cdot (-4) = a^2 + 16 \] - Since \( a^2 \geq 0 \) and \( 16 > 0 \), \( D > 0 \). The roots are **real and distinct**. 7. **Equation (vii):** \( 3x^2 + 7x + \frac{1}{2} = 0 \) - Coefficients: \( a = 3 \), \( b = 7 \), \( c = \frac{1}{2} \) - Discriminant: \[ D = 7^2 - 4 \cdot 3 \cdot \frac{1}{2} = 49 - 6 = 43 \] - Since \( D > 0 \), the roots are **real and distinct**. 8. **Equation (viii):** \( 3x^2 - 4\sqrt{3}x + 4 = 0 \) - Coefficients: \( a = 3 \), \( b = -4\sqrt{3} \), \( c = 4 \) - Discriminant: \[ D = (-4\sqrt{3})^2 - 4 \cdot 3 \cdot 4 = 48 - 48 = 0 \] - Since \( D = 0 \), the roots are **real and equal**. 9. **Equation (ix):** \( 2\sqrt{3}x^2 - 5x + \sqrt{3} = 0 \) - Coefficients: \( a = 2\sqrt{3} \), \( b = -5 \), \( c = \sqrt{3} \) - Discriminant: \[ D = (-5)^2 - 4 \cdot 2\sqrt{3} \cdot \sqrt{3} = 25 - 24 = 1 \] - Since \( D > 0 \), the roots are **real and distinct**. 10. **Equation (x):** \( (x - 2a)(x - 2b) = 4ab \) - Expanding gives: \( x^2 - 2(a + b)x + 4ab = 4ab \) - Rearranging gives: \( x^2 - 2(a + b)x = 0 \) - Coefficients: \( a = 1 \), \( b = -2(a + b) \), \( c = 0 \) - Discriminant: \[ D = (-2(a + b))^2 - 4 \cdot 1 \cdot 0 = 4(a + b)^2 \] - Since \( 4(a + b)^2 \geq 0 \), \( D \geq 0 \). The roots are **real** (either distinct or equal depending on \( a + b \)).
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