If "any number" on both sides is the same number. For example (sqr(4))2=(sqr(4))2. In other words if you remove multiplier of 2 from both sides, you have only sqr(any number) left. Thus (any number) has to be the same number on both sides or we can say any number to be "x" then "x" has to be on both sides in above example given as 4. I think in math it will make sense but in plain english it might confuse some people. I hope it makes sense.

(sqr(x))2= (sqr(x))2 is equal to

(sqr (x)) = (sqr (x))

where "x" is any number.

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