Question

Show that if a number is doubled,then it cube becomes eight times the cube of given number.

Answer 1

let n be any given number . 

now according to question m=2n; 
m^3 = (2n)^3 = 2^3 * n^3 = 8n^3. 

hence m^3 is eight times the cube of the given number n.

Answer 2

if 2^3= 8
then is double is 4 and
4^3 is 64
first answer is 8
according to question 8×8 should be equal to its double's cube I.e 64
8 × 8 =64.