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(3^(2x-1)+3^(2x-2)-3^(2x-4))<=315

(3^(2x-1)+3^(2x-2)-3^(2x-4))<=315 inequation

A inequation with variable

The solution

You have entered [src]
 2*x - 1    2*x - 2    2*x - 4       
3        + 3        - 3        <= 315
$$3^{2 x - 1} + 3^{2 x - 2} - 3^{2 x - 4} \leq 315$$
3^(2*x - 1*1) + 3^(2*x - 1*2) - 3^(2*x - 1*4) <= 315
Detail solution
Given the inequality:
$$3^{2 x - 1} + 3^{2 x - 2} - 3^{2 x - 4} \leq 315$$
To solve this inequality, we must first solve the corresponding equation:
$$3^{2 x - 1} + 3^{2 x - 2} - 3^{2 x - 4} = 315$$
Solve:
$$x_{1} = 3$$
$$x_{2} = \frac{\log{\left(27 \right)} + i \pi}{\log{\left(3 \right)}}$$
Exclude the complex solutions:
$$x_{1} = 3$$
This roots
$$x_{1} = 3$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} \leq x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{1}{10} + 3$$
=
$$\frac{29}{10}$$
substitute to the expression
$$3^{2 x - 1} + 3^{2 x - 2} - 3^{2 x - 4} \leq 315$$
$$- 3^{\left(-1\right) 4 + 2 \cdot \frac{29}{10}} + 3^{\left(-1\right) 2 + 2 \cdot \frac{29}{10}} + 3^{\left(-1\right) 1 + 2 \cdot \frac{29}{10}} \leq 315$$
     4/5       
105*3    <= 315
       

the solution of our inequality is:
$$x \leq 3$$
 _____          
      \    
-------•-------
       x_1
Solving inequality on a graph
Rapid solution 2 [src]
      log(27) 
(-oo, -------]
       log(3) 
$$x\ in\ \left(-\infty, \frac{\log{\left(27 \right)}}{\log{\left(3 \right)}}\right]$$
x in Interval(-oo, log(27)/log(3))
Rapid solution [src]
     log(27)
x <= -------
      log(3)
$$x \leq \frac{\log{\left(27 \right)}}{\log{\left(3 \right)}}$$
x <= log(27)/log(3)
The graph
(3^(2x-1)+3^(2x-2)-3^(2x-4))<=315 inequation