Same topic3 marksDifficulty: Medium
If a + b = 7 and ab = 12, find the value of a2 + b2.
Expansions
2 marksDifficulty: Easy
Expand: (2x + 3y)2.
Original Khojo Papers practice question — not from a past board paper.
Answer
4x2 + 12xy + 9y2
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Using (a + b)2 = a2 + 2ab + b2 with a = 2x and b = 3y gives 4x2 + 2(2x)(3y) + 9y2 = 4x2 + 12xy + 9y2.
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