The nth root of a number is a value such that . is the degree and is the radicand. Finding the nth root is the inverse of exponentiation to the nth power in the sense that . A root can be written with the symbol or with a fractional exponent. . When the radical symbol is written with no given radical, it is a square root (see below). Some examples of roots would be:
(since and )
The second root is often called the square root, while the third root the cubic root. Negative roots may be defined if the radicand is not zero and the degree is odd. Even roots may be imaginary if the radicand is negative.
Even degrees result in two answers, one positive and one negative. For example,
since and .
Babylonian Method - For Square Roots
This is the classical method for paper-pencil square rooting.
SQRT 7634169 =
1. First group the number you are rooting into groups of 2 digits. If there are an odd number, have 1 digit left at the beginning
SQRT 7|63|41|69 =
2. Take the first group of digits(Farthest left. It would be the one digit if your number has an odd number of digits) and find a number that is the largest whole number possible that when squared, is less than or equal to the first group of number(s). That is the first digit in the solution. Squaredouble the answer so far and subtract from the group of number(s).
SQRT 7|63|41|69 = 2 7 - 4 =3
3. Bring the second pair of numbers out and place them at the end of the leftover number.
'SQRT 7|63|41|69 = 2 363 '
Suppose the answer so far is x and the number you just got is y. You have to find a number (n) so that (20x+n)n is less than or equal to y. Once again, try to make n as big as possible. n is now the second digit in the solution. Subtract (20x+n)n from y to get you new y and the solution so far is x. Repeat step 3 until you are satisfied.
SQRT 7|63|41|69 = 27 47 x 7 = 329 363 - 329 = 34
SQRT 7|63|41|69 = 27 3441
SQRT 7|63|41|69 = 276 546 x 6 = 3276 3441 - 3276 = 165
SQRT 7|63|41|69 = 276 16569
SQRT 7|63|41|69 = 2763 5523 x 3 = 16569 16569 - 16569 = 0