This video teaches us the concept of nth roots. The video starts with the square root of constants. We find the number which when multiplies by itself for two times results in the constant inside the square root. Then we find the square root of variables. Here again the same concept is used. We find the variable which when multiplied by itself for two times results in the given variable. Then we find the cube root. Here we find the number which when multiplied by itself for three times results in the given number. Next we find the cube root of negative variables. Here the cube root will be negative as the minus sign remains after it is multiplied for three times. Square roots of a negative number are not real. We find the fourth root in the same way and generalize this for nth roots. This means we find the number which when multiplied by itself n times results in the given number. We find the nth roots of the numerator and denominator for finding the nth roots of fractions.