log2(4-x)=7 equation
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The solution
Detail solution
Given the equation
$$\frac{\log{\left(4 - x \right)}}{\log{\left(2 \right)}} = 7$$
$$\frac{\log{\left(4 - x \right)}}{\log{\left(2 \right)}} = 7$$
Let's divide both parts of the equation by the multiplier of log =1/log(2)
$$\log{\left(4 - x \right)} = 7 \log{\left(2 \right)}$$
This equation is of the form:
log(v)=p
By definition log
v=e^p
then
$$4 - x = e^{\frac{7}{\frac{1}{\log{\left(2 \right)}}}}$$
simplify
$$4 - x = 128$$
$$- x = 124$$
$$x = -124$$
Sum and product of roots
[src]
$$-124$$
$$-124$$
$$-124$$
$$-124$$