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log((x+7),2x+14)≥2 inequation

A inequation with variable

The solution

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log(x + 7, 2*x + 14) >= 2
$$\log{\left(x + 7 \right)} \geq 2$$
log(x + 7, 2*x + 14) >= 2
Detail solution
Given the inequality:
$$\log{\left(x + 7 \right)} \geq 2$$
To solve this inequality, we must first solve the corresponding equation:
$$\log{\left(x + 7 \right)} = 2$$
Solve:
$$x_{1} = - \frac{27}{4}$$
$$x_{1} = - \frac{27}{4}$$
This roots
$$x_{1} = - \frac{27}{4}$$
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
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$- \frac{27}{4} + - \frac{1}{10}$$
=
$$- \frac{137}{20}$$
substitute to the expression
$$\log{\left(x + 7 \right)} \geq 2$$
$$\log{\left(- \frac{137}{20} + 7 \right)} \geq 2$$
      log(2)      
1 - --------- >= 2
    log(3/10)     

but
      log(2)     
1 - --------- < 2
    log(3/10)    

Then
$$x \leq - \frac{27}{4}$$
no execute
the solution of our inequality is:
$$x \geq - \frac{27}{4}$$
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Solving inequality on a graph
Rapid solution [src]
And(-27/4 <= x, x < -13/2)
$$- \frac{27}{4} \leq x \wedge x < - \frac{13}{2}$$
(-27/4 <= x)∧(x < -13/2)
Rapid solution 2 [src]
[-27/4, -13/2)
$$x\ in\ \left[- \frac{27}{4}, - \frac{13}{2}\right)$$
x in Interval.Ropen(-27/4, -13/2)