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Logs help!

Given that log10(y+1) = 2-log10x, express y in terms of x as simply as possible.

Not really even sure where to start with this?

I tried to separate the left hand side by doing log10y x log101 is this right?
Reply 1
Original post by Natalie21
Given that log10(y+1) = 2-log10x, express y in terms of x as simply as possible.

Not really even sure where to start with this?

I tried to separate the left hand side by doing log10y x log101 is this right?


log10(y+1)=2log10x    log10(y+1)+log10x=2    log10(x(y+1))=2 \displaystyle log_{10}(y+1) = 2 - log_{10}x \implies log_{10}(y+1) + log_{10}x = 2 \implies log_{10}(x(y+1)) = 2

Now use the rule, logac=b    ab=c log_ac=b \implies a^b = c
yeah, excellent
Reply 3
Original post by raheem94
log10(y+1)=2log10x    log10(y+1)+log10x=2    log10(x(y+1))=2 \displaystyle log_{10}(y+1) = 2 - log_{10}x \implies log_{10}(y+1) + log_{10}x = 2 \implies log_{10}(x(y+1)) = 2

Now use the rule, logac=b    ab=c log_ac=b \implies a^b = c


Thank you :biggrin:

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