What is the value of x? Find it from the picture given below:

A logarithm is the inverse function to the exponential. For any a and x, loga(ax)=x\displaystyle log_a(a^x)= x.

8=23\displaystyle 8= 2^3 so 8=23/2\displaystyle \sqrt{8}= 2^{3/2} and 18=(12)3\displaystyle \frac{1}{\sqrt{8}}= \left(\frac{1}{\sqrt{2}}\right)^3.

4=22\displaystyle 4= 2^2 so 4x+1=(22)x+1=22(x+1)=22x+2\displaystyle 4^{x+1}= (2^2)^{x+1}= 2^{2(x+1)}= 2^{2x+2} so log2(4x+1)=2x+2\displaystyle log_2(4^{x+ 1})=2x+ 2.

It is the last logarithm that is the problem. There is no way to simplify log2(22x+2+22)\displaystyle log_2(2^{2x+2}+ 2^2).
 
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The LHS is 3. The RHS is 6 when x = 0 and 0 when x = -1. The solution is between -1 and 0. You need a numerical approach.
 
log base ab of ac=c/a.
This fact above will tell you exactly what the lhs equals.

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