The mathematical symbol you are talking about is an operator-the root sign, which is the inverse operation of the power. Just as the minus sign is the reciprocal of the plus sign, the division sign is the reciprocal of the multiplication sign. The root number in the computer is in the form of √, and no horizontal line is written. The number below the horizontal line is the scope of this operator. If there is a small mark 2 in the upper left corner of √, it is a square root, a small mark 3 in the upper left corner is a cubic root, and a small mark 4 in the upper left corner is a square root with four degrees. . . . .

In general, the small mark 2 of the square root is ignored, so the operation you mentioned above is to open the square root. It is the reciprocal of the square.

Like 2? = 4, so 2 = √(4) root number 4.

That is, 2*2 = 4, 2 = √(4) =√(2*2)

So when you say √(7*7), the result is =7.