Same chapter3 marksDifficulty: Medium
Evaluate (997)2 using a standard identity.
Expansions
3 marksDifficulty: Medium
Expand (a + b + c)2 and use it to evaluate (10 + 2 + 3)2 without direct multiplication.
Original Khojo Papers practice question — not from a past board paper.
Answer
a2 + b2 + c2 + 2ab + 2bc + 2ca, and the value is 225.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Substituting gives 100 + 4 + 9 + 2(20) + 2(6) + 2(30) = 113 + 40 + 12 + 60 = 225, which is 152.
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Same chapter1 markDifficulty: Medium
If x + 1/x = 3, then x2 + 1/x2 is:
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