How Do You Solve Exponential Equations Using Logarithms?

AI Thread Summary
To solve the exponential equation 12^x = 4 * 8^(2x), logarithms are utilized. Taking the logarithm of both sides allows for simplification using the properties of logarithms, such as log(a*b) = log(a) + log(b) and log(a^b) = b*log(a). The discussion emphasizes the importance of applying these logarithmic rules to break down the equation. Participants encourage clarity in the steps rather than assuming prior knowledge of logarithmic concepts. Ultimately, the solution hinges on correctly applying logarithmic properties to simplify and solve for x.
moe11
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Homework Statement


12^x=4X8^(2x)

Big X= multiplication sign
little x= unknown

i simply cannot figure this out. Any help please?

Homework Equations


4.6X1.06^(2x+3)=5X3^(x)
 
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Use logarithms! Isn't that your title? Take the log of both sides and use the rules of logarithms to simplify. What do you get?
 


Dick said:
Use logarithms! Isn't that your title? Take the log of both sides and use the rules of logarithms to simplify. What do you get?

i wouldn't post this if i could do it as easily as you said. Can you explain? Thats why I'm here.
 


log(12^x)=log(4*8^(2x)). That wasn't so hard. Now simplify it. Use rules of logarithms like, log(a*b)=log(a)+log(b), log(a^b)=b*log(a).
 


Your equation is 12x=(4)82x.

Since you titled this "logarithms", Dick assumed you knew some basic rules of logarithms. Take the logarithm of both sides: log(12x= log((4)82x)

Now use the fact that log(ab)= log(a)+ log(b) and that log(ax)= x log(a).
 
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