Online Course Discussion Forum

Math Challenge III Algebra 1.32

 
 
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Math Challenge III Algebra 1.32
by Raymond luo - Tuesday, June 16, 2020, 4:42 PM
 

For 1.32, I don't really know where to start. I'm given a bunch of terms that don't have a common base or. Could I try a change of base?

 
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Re: Math Challenge III Algebra 1.32
by Dr. Kevin Wang - Tuesday, June 16, 2020, 7:09 PM
 

Yes, the bases are different, so the first thing you can do is to change to a common base.

Note: the problem in question is the following:

Let $n$ be an even positive integer, solve the inequality for $x$: \[ \log_2 x - 4\log_{2^2} x + 12\log_{2^3} x +\cdots +n(-2)^{n-1}\log_{2^n} x > \frac{1-(-2)^n}{3}\log_2(x^2-2) \]

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Re: Math Challenge III Algebra 1.32
by Raymond luo - Thursday, June 18, 2020, 11:32 AM
 

Ok Thank you! I think I got it.