Question 59 (a)
What should be added to x3+3x2y+3xy2+y3 to get x3+y3?
In order to find the solution subtract x3+3x2y+3xy2+y3 from x3+y3.
Required expression is
x3+y3−(x3+3x2y+3xy2+y3)=x3+y3−x3−3x2y−3xy2−y3
On combining the like terms.
=x3−x3+y3−y3−3x2y−3xy2=−3x2y−3xy2
So, if we add −3x2y−3xy2 in x3+3x2y+3xy2+y3, we get x3+y3.