Q.3 Find the smallest number by which each of the following numbers must be divided to obtain a perfect cube.
(i) 81
(ii) 128
(iii) 135
(iv) 192
(v) 704
By prime factorization of given numbers :
(i) 81 :
So given number needs to be divided by 3 to get a perfect cube.
(ii) 128 : .
So the given number needs to be divided by 2 to get a perfect cube.
(iii) 135 :
So the given number needs to be divided by 5 to get a perfect cube.
(iv) 192 :
So the given number needs to be divided by 3 to get a perfect cube.
(v) 704 :
So the given number needs to be divided by 11 to get a perfect cube.