Solved UPSC CDS/OTA Question
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Q · AlgebraMedium · 45s
If m - 5n = 2 then the value of m₃ - 125n₃ - 30mn is:
TopicAlgebra
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
The complete worked solution.
Every step explained - no skipped algebra.
Given that, m - 5n = 2
On cubing, (m - 5n)3 = 8
⇒ m₃ - 125n₃ - 3m.5n(m - 5n) = 8
⇒ m₃ - 125n₃ - 15mn(m - 5n) = 8
⇒ m₃ - 125n₃ - 30mn = 8
Final Answer: Option A - 9