CUET Preparation Today
CUET
General Test
Quantitative Reasoning
Algebra
If x4 + x2y2 + y4 = 126,
x2 + xy + y2 = 42, then
find x2 - xy + y2 .
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Formula → x4 + y4 + x2y2 = (x2 + y2 + xy) × (x2 + y2 - xy)
⇒ 126 = 42 × (x2 + y2 - xy)
⇒ x2 + y2 - xy = \(\frac{126}{42}\) = 3
