Change of base formula proof | Logarithms | Algebra II | Khan Academy

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[BryanCarthell]

I love that you actually prove these things instead of just putting it out there and saying, "that's just how it is"

[BryanCarthell]

I think fewer people would get lost if they could see how these things work. Thank you for all your work!

[abir_existz]

Thanks a lot, sir! You have helped a lot of students who feel lost when they learn these formulas with no explanation as to how they work!

[annomanno]

Why is the proof so simple, I've spent all night filling up multiple pages just to get nothing and here comes along this guy and does it under 5 minutes. It's so stressful being in this position. Thanks for the proof. 👍

[RohitKumar-pihu]

Sir,
I have question!
If lnx-lny=a, lny-lnz=b, lnz-lnx=c.then value of( x/y) ^ b-C .( y/z)^ c-a .(z/x) ^ a-b=?

[jakeday]

mocks in like 2 weeks, this was not taught by my teacher, thank you!

[internationalremixes]

u made it too easy...thanku so much....

[LeoLerena]

Just because we can. If you multiply both sides by the same, the equality remains as before.

[mwql]

very nice, thanks! i find the cursor distracting, whenever the font colour is changed. However, the proof is really useful :)

[ahmadimam]

thank-you, it is help full but quite difficult to understand

[arnauadell]

you really need some hotkeys for colours :)

[sleepycat]

Thank you, you save me. My fcking school dont tell me how is this formula come from, they just tell me to memorize it.

[seandafny]

Yes indeed a drumroll would be well justified.

[raniellabiancacoronado]

Why do we have to multiply both sides by log base b? Thanks. :)

[Vijay_helo]

Is it y.logba or y^logba ??? if it is in power how can we canel them sir?

[qualquan]

okay, another way of proving base change formula

[anatollegros]

But, couldn't "y" be equal to anything? Couldn't we "proove" this way any statment?

[monickverma]

3:30 u didn't need to solve y in terms of logarithm base b instead u could have taken logarithm of a at base b to the other side od the equation which will gove the value of y .