History of Hindu Mathematics: A Source Book v2.c17.s3.54

v2.c17.s3.54

“The square of a positive and a negative number is positive. It will become what it was in the case of the square-root. A negative number by itself is non-square, so its square-root is unreal; so the rule (for the square-root) should be applied in the case of a positive number.”3