SOLUTION: 3^x<5^x

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Question 1063781: 3^x<5^x
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!

3%5Ex%22%22%3C%22%225%5Ex

Since logarithms of numbers are in the same
order of inequality as the numbers they are the
logarithms of, we can take the logs of both 
sides and retain the same inequality symbol <

log%28%283%5Ex%29%29%22%22%3C%22%22log%28%285%5Ex%29%29

Now we use the rule of logarithms that allows 
us to move the exponent of what the logarithm 
is of -- out in front of the logarithm as its 
coefficient:

x%2Alog%28%283%29%29%22%22%3C%22%22x%2Alog%28%285%29%29

x%2A0.4771212547%22%22%3C%22%22x%2A0.6989700043

Get 0 on the right by subtracting the entire
right side from both sides:

x%2A0.4771212547-x%2A0.6989700043%22%22%3C%22%220

Factor out x on the left

x%280.4771212547-0.6989700043%29%22%22%3C%22%220

x%28-0.221848796%29%22%22%3C%22%220

Divide both sides by -0.221848796, and since we are
dividing both sides by a negative number, we must
reverse the inequality sign from < to > :

x%28-0.221848796%29%2F%28-0.221848796%29%22%22%3E%22%220%2F%28-0.221848796%29

x%22%22%3E%22%220   <--solution

Edwin