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16^x-9<1 inequation

A inequation with variable

The solution

You have entered [src]
  x        
16  - 9 < 1
16x9<116^{x} - 9 < 1
16^x - 9 < 1
Detail solution
Given the inequality:
16x9<116^{x} - 9 < 1
To solve this inequality, we must first solve the corresponding equation:
16x9=116^{x} - 9 = 1
Solve:
Given the equation:
16x9=116^{x} - 9 = 1
or
(16x9)1=0\left(16^{x} - 9\right) - 1 = 0
or
16x=1016^{x} = 10
or
16x=1016^{x} = 10
- this is the simplest exponential equation
Do replacement
v=16xv = 16^{x}
we get
v10=0v - 10 = 0
or
v10=0v - 10 = 0
Move free summands (without v)
from left part to right part, we given:
v=10v = 10
do backward replacement
16x=v16^{x} = v
or
x=log(v)log(16)x = \frac{\log{\left(v \right)}}{\log{\left(16 \right)}}
x1=10x_{1} = 10
x1=10x_{1} = 10
This roots
x1=10x_{1} = 10
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
x0<x1x_{0} < x_{1}
For example, let's take the point
x0=x1110x_{0} = x_{1} - \frac{1}{10}
=
110+10- \frac{1}{10} + 10
=
9910\frac{99}{10}
substitute to the expression
16x9<116^{x} - 9 < 1
9+169910<1-9 + 16^{\frac{99}{10}} < 1
                   3/5    
-9 + 549755813888*2    < 1
    

but
                   3/5    
-9 + 549755813888*2    > 1
    

Then
x<10x < 10
no execute
the solution of our inequality is:
x>10x > 10
         _____  
        /
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       x1
Solving inequality on a graph
-5.0-4.0-3.0-2.0-1.05.00.01.02.03.04.0-5050
Rapid solution [src]
    log(10)
x < -------
    log(16)
x<log(10)log(16)x < \frac{\log{\left(10 \right)}}{\log{\left(16 \right)}}
x < log(10)/log(16)
Rapid solution 2 [src]
      log(10) 
(-oo, -------)
      log(16) 
x in (,log(10)log(16))x\ in\ \left(-\infty, \frac{\log{\left(10 \right)}}{\log{\left(16 \right)}}\right)
x in Interval.open(-oo, log(10)/log(16))