logs (c2) Watch

em_cart
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#1
Report Thread starter 7 years ago
#1
Right, well I'm pretty sure this is a pretty simple c2 logs question but I have tried several ways for it to work and I still can't get the right answer!

The question is:

Log432 - log46 + log412

Help would be greatly appreciated - thank you in advance!
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Arsey
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#2
Report 7 years ago
#2
learn your log rules

log a + log b = log ab

log a - log b = log a/b

these work for any base

so you have

log4(32) + log4(12) - log4(6)

This is combined to give

log4(32*12/6)

log4(64)

you can evaluate this easily on your calc using the log to any base button, on older calculators you would need to say

log4(64) = x

take log4 over to the other side gives

64 = 4^x

x = 3, most of the time the power is obvious, if not log both sides (as in log10 the log button)and solve.
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mir3a
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#3
Report 7 years ago
#3
(Original post by em_cart)
Right, well I'm pretty sure this is a pretty simple c2 logs question but I have tried several ways for it to work and I still can't get the right answer!

The question is:

Log432 - log46 + log412

Help would be greatly appreciated - thank you in advance!
When you minus logs of the same base, always divide one by the other. When adding, multiply.
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em_cart
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#4
Report Thread starter 7 years ago
#4
(Original post by Arsey)
learn your log rules

log a + log b = log ab

log a - log b = log a/b

these work for any base

so you have

log4(32) + log4(12) - log4(6)

This is combined to give

log4(32*12/6)

log4(64)

you can evaluate this easily on your calc using the log to any base button, on older calculators you would need to say

log4(64) = x

take log4 over to the other side gives

64 = 4^x

x = 3, most of the time the power is obvious, if not log both sides (as in log10 the log button)and solve.
Ohhh! I see! I get it now, thank you very much
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Jampolo
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#5
Report 7 years ago
#5
Check out my YouTube channel below for logs help next time if you'd like
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em_cart
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#6
Report Thread starter 7 years ago
#6
(Original post by Jampolo)
Check out my YouTube channel below for logs help next time if you'd like
Cool, thanks, will do
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