What is sqrt(2x^3)*sqrt(6x^2)*sqrt(10x)√2x3⋅√6x2⋅√10x in simplified form?
1 Answer
Explanation:
Note that if
sqrt(a)sqrt(b) = sqrt(ab)√a√b=√ab
By extension, we find if
sqrt(a)sqrt(b)sqrt(c) = sqrt(ab)sqrt(c) = sqrt(abc)√a√b√c=√ab√c=√abc
Note also that if
sqrt(a^2) = a√a2=a
In our example, we will assume
So in our example:
sqrt(2x^3)*sqrt(6x^2)*sqrt(10x) = sqrt(2x^3*6x^2*10x)√2x3⋅√6x2⋅√10x=√2x3⋅6x2⋅10x
color(white)(sqrt(2x^3)*sqrt(6x^2)*sqrt(10x)) = sqrt(2x^3*2x^3*30)√2x3⋅√6x2⋅√10x=√2x3⋅2x3⋅30
color(white)(sqrt(2x^3)*sqrt(6x^2)*sqrt(10x)) = sqrt((2x^3)^2)sqrt(30)√2x3⋅√6x2⋅√10x=√(2x3)2√30
color(white)(sqrt(2x^3)*sqrt(6x^2)*sqrt(10x)) = 2x^3 sqrt(30)√2x3⋅√6x2⋅√10x=2x3√30
Footnote
It seems to be a common error to assume that:
sqrt(x^2) = x√x2=x
This does hold, but only if
If we want to cover the case
sqrt(x^2) = abs(x)√x2=|x|
In the given example, we can deduce that the case