Question

49 test weather the following are perfect cubes using prime factorisation meathod​

Answer 1

Answer:

1331

Step-by-step explanation:

a) Factors of 128,

128=  

2×2×2

​

×  

2×2×2

​

×2

As grouping in triplets, 2 is not grouped.

So, 128 is not a perfect cube.

b) Factors 343,

343=  

7×7×7

​

 

As grouping in triplets, all the numbers are grouped.  

So, 343 is a perfect cube.

c) Factors of 729,

729=  

3×3×3

​

×  

3×3×3

​

 

As grouping in triplets, all the numbers are grouped.

So, 729 is a perfect cube.

d) Factors of 1331,

1331=11×11×11

As grouping in triplets, all the numbers are grouped.

So, 1331 is a perfect cube.