log2(5x+8)=log23+4 equation
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The solution
Detail solution
Given the equation
$$\frac{\log{\left(5 x + 8 \right)}}{\log{\left(2 \right)}} = \log{\left(23 \right)} + 4$$
$$\frac{\log{\left(5 x + 8 \right)}}{\log{\left(2 \right)}} = \log{\left(23 \right)} + 4$$
Let's divide both parts of the equation by the multiplier of log =1/log(2)
$$\log{\left(5 x + 8 \right)} = \left(\log{\left(23 \right)} + 4\right) \log{\left(2 \right)}$$
This equation is of the form:
log(v)=p
By definition log
v=e^p
then
$$5 x + 8 = e^{\frac{\log{\left(23 \right)} + 4}{\frac{1}{\log{\left(2 \right)}}}}$$
simplify
$$5 x + 8 = 2^{\log{\left(23 \right)} + 4}$$
$$5 x = -8 + 2^{\log{\left(23 \right)} + 4}$$
$$x = - \frac{8}{5} + \frac{2^{\log{\left(23 \right)} + 4}}{5}$$
Sum and product of roots
[src]
log(23)
8 16*2
- - + -----------
5 5
$$- \frac{8}{5} + \frac{16 \cdot 2^{\log{\left(23 \right)}}}{5}$$
log(23)
8 16*2
- - + -----------
5 5
$$- \frac{8}{5} + \frac{16 \cdot 2^{\log{\left(23 \right)}}}{5}$$
log(23)
8 16*2
- - + -----------
5 5
$$- \frac{8}{5} + \frac{16 \cdot 2^{\log{\left(23 \right)}}}{5}$$
log(23)
8 16*2
- - + -----------
5 5
$$- \frac{8}{5} + \frac{16 \cdot 2^{\log{\left(23 \right)}}}{5}$$
log(23)
8 16*2
x1 = - - + -----------
5 5
$$x_{1} = - \frac{8}{5} + \frac{16 \cdot 2^{\log{\left(23 \right)}}}{5}$$
x1 = -8/5 + 16*2^log(23)/5