log10(x)*20=-15 equation
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The solution
Detail solution
Given the equation
$$20 \frac{\log{\left(x \right)}}{\log{\left(10 \right)}} = -15$$
$$\frac{20 \log{\left(x \right)}}{\log{\left(10 \right)}} = -15$$
Let's divide both parts of the equation by the multiplier of log =20/log(10)
$$\log{\left(x \right)} = - \frac{3 \log{\left(10 \right)}}{4}$$
This equation is of the form:
log(v)=p
By definition log
v=e^p
then
$$x = e^{- \frac{15}{20 \frac{1}{\log{\left(10 \right)}}}}$$
simplify
$$x = \frac{\sqrt[4]{10}}{10}$$
4 ____
\/ 10
x1 = ------
10
$$x_{1} = \frac{\sqrt[4]{10}}{10}$$
Sum and product of roots
[src]
$$\frac{\sqrt[4]{10}}{10}$$
$$\frac{\sqrt[4]{10}}{10}$$
$$\frac{\sqrt[4]{10}}{10}$$
$$\frac{\sqrt[4]{10}}{10}$$