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If the equation x^(4)+bx^(3)y+cx^(2)y^(2...

If the equation `x^(4)+bx^(3)y+cx^(2)y^(2)+dxy^(3)+ey^(4)=0` represent two pairs of perpendicular lines, then

A

`b+d=1 and e=-1`

B

`b+d=0 and e=-1`

C

`b+d=0 and e=1`

D

none of these

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The correct Answer is:
To solve the problem, we need to determine the conditions under which the equation \( x^4 + bx^3y + cx^2y^2 + dxy^3 + ey^4 = 0 \) represents two pairs of perpendicular lines. ### Step-by-Step Solution: 1. **Understanding the Equation**: The given equation is a quartic equation in two variables \( x \) and \( y \). For it to represent two pairs of perpendicular lines, it can be factored into the product of two quadratic equations. 2. **Assuming the Form of the Quadratics**: We can assume that the equation can be expressed as: \[ (x^2 + \alpha xy - y^2)(x^2 + \beta xy - y^2) = 0 \] where \( \alpha \) and \( \beta \) are constants. 3. **Expanding the Product**: Expanding the product gives: \[ x^4 + (\alpha + \beta)x^3y + (\alpha\beta - 2)x^2y^2 + (-\alpha - \beta)xy^3 + y^4 = 0 \] 4. **Comparing Coefficients**: Now we compare the coefficients of the expanded form with the original equation: - Coefficient of \( x^3y \): \( b = \alpha + \beta \) - Coefficient of \( x^2y^2 \): \( c = \alpha\beta - 2 \) - Coefficient of \( xy^3 \): \( d = -(\alpha + \beta) \) - Coefficient of \( y^4 \): \( e = 1 \) 5. **Conditions for Perpendicular Lines**: For the lines to be perpendicular, the product of the slopes of the two lines must equal -1. This leads to the condition: \[ \alpha \beta = -1 \] 6. **Using the Conditions**: From the equations derived: - Since \( e = 1 \), we have \( e = 1 \). - From \( d = -(\alpha + \beta) \) and \( b = \alpha + \beta \), we can conclude: \[ b + d = 0 \] 7. **Final Conditions**: Thus, the conditions we have derived are: - \( e = 1 \) - \( b + d = 0 \) - \( \alpha \beta = -1 \) ### Summary of Results: The equation \( x^4 + bx^3y + cx^2y^2 + dxy^3 + ey^4 = 0 \) represents two pairs of perpendicular lines if: - \( e = 1 \) - \( b + d = 0 \)

To solve the problem, we need to determine the conditions under which the equation \( x^4 + bx^3y + cx^2y^2 + dxy^3 + ey^4 = 0 \) represents two pairs of perpendicular lines. ### Step-by-Step Solution: 1. **Understanding the Equation**: The given equation is a quartic equation in two variables \( x \) and \( y \). For it to represent two pairs of perpendicular lines, it can be factored into the product of two quadratic equations. 2. **Assuming the Form of the Quadratics**: ...
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