Solve for .
Answer and explanation
Correct answer: C. 3
- Step 1: Write 81 as a power of 3: . Step 2. Equate the indices: , so . Answer: 3. Why not the others: 4: That ignores the in the index. 5: That adds 1 where it should be subtracted. 2: That divides the power by 2.
Practise more Surds, indices and logarithms.
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