If (x+x+x) = x*x*x and x <>0 (x is not zero) then what’s the value of x?
I like this one a lot because x=0 would be an obvious answer and it’s taken away, and then when you plot it, you get 2 correct answers. Let’s see how it’s done…
(x+x+x) = x*x*x
so, 3x=x^3
or 3 = x^2 (after diving by x)
therefore x = sqrt(3)
x=√3
Nice! But we also know that negative number * negative number also makes the output positive. So, let’s plot the equations…
Aha, there seems to be 2 possibilities: one on the left side (negative) and one on the right side (positive). So, the correct answers are:
x=√3
and x=−√3
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