Solved UPSC CDS/OTA Question
A solved UPSC CDS/OTA PYQ — decoded step-by-step.
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Q · LogarithmMedium · 45s
log₂(9–2x)=10log(3 – x). Solve for x.
TopicLogarithm
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.
For x = 0, we have LHS
Log₂ 8 = 3.
RHS : 10log₃ = 3.
We do not get LHS = RHS for either x
= 3 or x = 6.
Thus, option (a) is correct.
Final Answer: Option A — 0