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lg²x+2lgx=8 equation

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Numerical solution:

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The solution

You have entered [src] 
   2                  
log (x) + 2*log(x) = 8
log⁡(x)2+2log⁡(x)=8\log{\left(x \right)}^{2} + 2 \log{\left(x \right)} = 8
Simplify
The graph
-2.50.02.55.07.510.012.515.017.520.022.525.0-100100
Plot the graph f1(x)
Plot the graph f2(x)
Rapid solution [src] 
      -4
x1 = e
x1=e−4x_{1} = e^{-4} 
      2
x2 = e
x2=e2x_{2} = e^{2} 
x2 = exp(2)
Sum and product of roots [src] 
sum
 -4    2
e   + e
e−4+e2e^{-4} + e^{2} 
=
 -4    2
e   + e
e−4+e2e^{-4} + e^{2} 
product
 -4  2
e  *e
e2e4\frac{e^{2}}{e^{4}} 
=
 -2
e
e−2e^{-2} 
exp(-2)
Numerical answer [src] 
x1 = 7.38905609893065
x2 = 7.38905609893065 - 9.08134065356179e-17*i
x2 = 7.38905609893065 - 9.08134065356179e-17*i
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