how do i solve this? 7^2t-1=35
do you mean \[ \Large 7^{2t}-1=35 \]
no it's 2t-l in the exponent
\[7^{2t-1} = 35\] huh
you take the log
\[\log_7 35 = 2t - 1\]
\[\log_7 35 + 1 = 2t\]
\[\frac{\log_7 35 + 1}{2} = t\]
using my notes, im supposed to solve it this way 2t log7-log7=log35
oh i see...that's possible...do you want to know where it came from?
i know how to get to that point but dont know where to go from there
take the log of both sides \[(2t-1)\log 7 = \log 35\] distribute \[2t\log 7 - \log 7 = \log 35\] \[2t \log 7 = \log 35 + \log 7\] \[2t = \frac{\log(35 \times 7)}{\log 7}\] \[t = \frac{\log (35\times 7)}{2\log 7}\]
hah lol
\[t = \frac{\log 245}{2\log 7}\] \[t = \frac 12 \frac{\log 245}{\log 7}\] \[t = \frac 12 \log_7 245\]
\[t = \log_7 \sqrt{245}\]
im not sure if that's same as what i initially wrote though
the final rounded answer should come to 1.41 i just have no idea how to get to that
if you have a calculator just type if what @lgbasallote wrote first \[ \Large t=\frac{\log 245}{2\log 7}=1.413543... \]
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