Mister Exam

Other calculators

1/4^(x+4)>8√2 inequation

A inequation with variable

The solution

You have entered [src]
 -4 - x       ___
4       > 8*\/ 2 
$$\left(\frac{1}{4}\right)^{x + 4} > 8 \sqrt{2}$$
(1/4)^(x + 4) > 8*sqrt(2)
Detail solution
Given the inequality:
$$\left(\frac{1}{4}\right)^{x + 4} > 8 \sqrt{2}$$
To solve this inequality, we must first solve the corresponding equation:
$$\left(\frac{1}{4}\right)^{x + 4} = 8 \sqrt{2}$$
Solve:
Given the equation:
$$\left(\frac{1}{4}\right)^{x + 4} = 8 \sqrt{2}$$
or
$$\left(\frac{1}{4}\right)^{x + 4} - 8 \sqrt{2} = 0$$
or
$$\frac{4^{- x}}{256} = 8 \sqrt{2}$$
or
$$\left(\frac{1}{4}\right)^{x} = 2048 \sqrt{2}$$
- this is the simplest exponential equation
Do replacement
$$v = \left(\frac{1}{4}\right)^{x}$$
we get
$$v - 2048 \sqrt{2} = 0$$
or
$$v - 2048 \sqrt{2} = 0$$
Expand brackets in the left part
v - 2048*sqrt2 = 0

Divide both parts of the equation by (v - 2048*sqrt(2))/v
v = 0 / ((v - 2048*sqrt(2))/v)

do backward replacement
$$\left(\frac{1}{4}\right)^{x} = v$$
or
$$x = - \frac{\log{\left(v \right)}}{\log{\left(4 \right)}}$$
$$x_{1} = 2048 \sqrt{2}$$
$$x_{1} = 2048 \sqrt{2}$$
This roots
$$x_{1} = 2048 \sqrt{2}$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} < x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + 2048 \sqrt{2}$$
=
$$- \frac{1}{10} + 2048 \sqrt{2}$$
substitute to the expression
$$\left(\frac{1}{4}\right)^{x + 4} > 8 \sqrt{2}$$
$$\left(\frac{1}{4}\right)^{4 + \left(- \frac{1}{10} + 2048 \sqrt{2}\right)} > 8 \sqrt{2}$$
   39          ___          
 - -- - 2048*\/ 2        ___
   10              > 8*\/ 2 
4                    
          

Then
$$x < 2048 \sqrt{2}$$
no execute
the solution of our inequality is:
$$x > 2048 \sqrt{2}$$
         _____  
        /
-------ο-------
       x1
Solving inequality on a graph
Rapid solution [src]
   /                     /    ___\\
   |                  log\8*\/ 2 /|
And|-oo < x, x < -4 - ------------|
   \                     log(4)   /
$$-\infty < x \wedge x < -4 - \frac{\log{\left(8 \sqrt{2} \right)}}{\log{\left(4 \right)}}$$
(-oo < x)∧(x < -4 - log(8*sqrt(2))/log(4))
Rapid solution 2 [src]
              /    ___\ 
           log\8*\/ 2 / 
(-oo, -4 - ------------)
              log(4)    
$$x\ in\ \left(-\infty, -4 - \frac{\log{\left(8 \sqrt{2} \right)}}{\log{\left(4 \right)}}\right)$$
x in Interval.open(-oo, -4 - log(8*sqrt(2))/log(4))