x+y=2 , x3+y3+6xy=?
সমাধান
সঠিক উত্তর: Option C
x3+y3+6xy=x3+y3+3×2×xy
=x3+y3+3(x+y).xy [x+y=2]
=x3+y3+3xy(x+y)
=(x+y)3
=(2)3
=8
=x3+y3+3(x+y).xy [x+y=2]
=x3+y3+3xy(x+y)
=(x+y)3
=(2)3
=8