Some LOGs help please! (1 Viewer)

0hNivlek

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So my school gave us holiday hw but i don't understand some of it. How do you solve these?

1. If a ^ (2.37) = 10, find:
a) log a 10

2. Express as a logarithm to the given base:
a) log 4 ^ 11 (base 2)

Thanks!
 

gurmies

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1. If a ^ (2.37) = 10, find:
a) log a 10

2. Express as a logarithm to the given base:
a) log 4 ^ 11 (base 2)

1 a) log a 10 = 2.37

2 a) logbase2 (4^11)/logbase2 (10) - assuming initial base was 10
 
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alcalder

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The thing with logs is, they are reciprocals of powers.

1. So, if something to a power is 10
eg a 2.37 = 10

Then the reciprocal is, the log (to the base of the number you are using in the power) of the answer is the power.
log a 10 = 2.37

2. If you want to change the base from say "10" (assumed if no log base is given) to "2", you divide as shown:

log 10 411= log2411 / log210

=log222(11) / log210
=log2222 / log210
=22/log210
 

Trebla

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They're not "reciprocals". They're called "inverses".
 

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