The smallest integer for which holds, is closest to
The smallest integer for which holds, is closest to
Solution
We need to find the smallest integer such that .
Comparing these huge numbers directly is impossible! We need a smarter approach.
When we have equations or inequalities with different bases and exponents, logarithms are our best friend. They convert multiplication into addition and powers into multiplication.
If (where ), then .
Starting with:
Take the natural logarithm of both sides:
Use the logarithm property :
Solve for :
We need to find and :
For : Since , we have
For :
Substituting:
Since we need the smallest integer such that , and we found , the answer is:
For : would be slightly smaller than
For : is the first power of 4 that exceeds
When comparing exponential expressions with different bases, logarithms transform the problem into simple arithmetic!
Therefore, the smallest integer is 39.
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