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Trig and log problem

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Lnlsec(x)l=-Lnlcos(x)l

January 6, 2011

4 Comments • Newest first

koreankid36

I'm not sure if I'm correct because I forgot most of my trig... but.. here I go o-o:

Lnlsec(x)l = Lnl1/cosxl = Lnl1l- Lnlcosxl (and because ln1=0) = -Lnlcosxl

yup ... I think that's how to do it..

Reply January 6, 2011
jonatan

sec(x) = 1/cos(x)

Lnlsec(x)l=-Lnlcos(x)l

Gives us:
I: e^(Lnlsec(x)l)
II: e^(-Lnlcos(x)l)

Next step:
I: e^(Lnlsec(x)l)=|sec(x)|=|1/cos(x)|=1/|cos(x)|
II: e^(-Lnlcos(x)l) = 1/e^(Lnlcos(x)l) = 1/|cos(x)|

I = II

Maybe something like that?

Reply January 6, 2011
Xgo321

:o Omg is that all? seems so short.. D: Ahh wtheck can't work with those numbers.

Reply January 6, 2011
darksuitguy

[quote=KidZombie]Those arent numbers.[/quote]

You need to learn math.
Ln means natural log (log base e), while lxl means absolute value of x.

Reply January 6, 2011 - edited