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JEE MainMathematicsModerateStraight Lines

If equation 4y3−8a2yx2−3ay2x+8x3=04y^{3} - 8a^{2}yx^{2} - 3ay^{2}x + 8x^{3} = 0
represents three straight lines, two of which are perpendicular to each

other, then find sum of all possible values of a.;fn lehdj.k
4y3−8a2yx2−3ay2x+8x3=04y^{3} - 8a^{2}yx^{2} - 3ay^{2}x + 8x^{3} = 0rhu ljy
a

Show answer and solution
4m3−3am2−8a2m+8=04m^{3} - 3am^{2} - 8a^{2}m + 8 = 0
⇒m1m2m3=−2\Rightarrow m_{1}m_{2}m_{3} = - 2 ⇒m3=2\Rightarrow m_{3} = 2
⇒4(2)3−3a(4)−16a2+8=0\Rightarrow 4(2)^{3} - 3a(4) - 16a^{2} + 8 = 0
 sum =−1216\ sum\ = - \frac{12}{16}

Source: Grass-G / M-27 Mathematics Paper 2 15 Jan.docx

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