Question

What should be added to x3+3x2y+3xy2+y3 to get + x3+y3?​

Answer 1

Answer:

let the number be 'a'

3x+6xy+6xy+3y+a=3x+3y

3x+3y+12xy+a=3x+3y

12xy+a=3x+3y-(3x+3y)

12xy+a=0

therefore a= -12xy

so, -12xy should be added to 3x+3x2y+3xy2+y3 to get x3+y3

Answer 2

Answer:

3x+3xy+6xy+3y

-(3x+3y)

12xy+a=0