Evaluate http://curriculum.kcdistancelearning...t4_Exam_25.gif

Please show work :)

I got that the answer is 4 because 7^{log7}= 1

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- Jan 31st 2013, 07:29 AMdzombergEvaluate a logarithmic function
Evaluate http://curriculum.kcdistancelearning...t4_Exam_25.gif

Please show work :)

I got that the answer is 4 because 7^{log7}= 1 - Jan 31st 2013, 07:43 AMebainesRe: Evaluate a logarithmic function
I would suggest that you start with the definition of the logarthm: If $\displaystyle a^b = c$ then $\displaystyle \log_a c = b$. Here 'a' is 7 and 'b' is $\displaystyle \log_7 4$, therefore from the right hand side of the definition $\displaystyle \log_7 c = b = log_7 4$. Hence c = 4, and $\displaystyle 7^{\log_7 4} = 4$.

- Jan 31st 2013, 09:00 PMibduttRe: Evaluate a logarithmic function
You are absolutely right. You can also proceed like this. Let c = 7^(ln4 to the base 7) taking log on both sides we get (lnc to the base 7) = (ln4 to the base 7) and that gices c = 4. Hence 7^(ln4 to the base 7)= 4