RAÍZ CUADRADA DE 4 NO ES 2 Y -2

Square root of 4 is not 2 and -2, but simply 2. Some highly relevant YouTubers in mathematics, and hundreds of thousands of teachers in their classrooms, claim every day that square roots with an even exponent can take two values, one positive and one negative. To avoid this error, one would simply have to refer to the definition of the square root or any other even exponent that can be found in any book on the subject: they are functions whose domain in R is [0, ∞) and whose range is also [0, ∞). In the video, I state that I have the impression that this widespread error stems from confusing, for example, the solutions of a second-degree equation with the square root. I try to explain the situation by analyzing the equation y²=x. If we assume that x=4, then y can indeed be 2 and -2. This equation has two branches. One of them, the positive one, is precisely the square root function. In addition to analyzing the problem with the root of four, we also look at the fourth root of 16. #cacaticas Become a member of MATHEMATICS WITH JUAN    / @matematicaconjuan