Question

prove that if a number is doubled, then it's cube is eight times the cube of the given number

Answer 1

let the no.be x
so its double is 2x
Now, (2x)^3=8x^3
Also,8×(x)^3=8x^3
Hence,it is proved

Answer 2

let the no be X then when doubled it become 2X thus

on cubing (2X)^3 we get 2x*2x*2x = 8x^3

and the cube of orignal no x was x^3 thus we see that by making double and cubing we get a no 8 times larger

as 8*x3 is 8 times of x3