Subtract: x3 + 2x2y + 6xy2 − y3 from y3−3xy2−4x2y

1.	Subtract: x3 + 2x2y + 6xy2 − y3 from y3−3xy2−4x2y
Answer» Given x³ + 2x²y + 6xy² − y³ and y³−3xy²−4x²y = (y³ – 3xy² – 4x²y) – (x³ + 2x²y + 6xy² – y³) = y³ – 3xy² – 4x²y – x³ – 2x²y – 6xy² + y³ = y³ + y³– 3xy²– 6xy²– 4x²y – 2x²y – x³ = 2y³– 9xy² – 6x²y – x³

Answer»

Given x³ + 2x²y + 6xy² − y³ and y³−3xy²−4x²y

= (y³ – 3xy² – 4x²y) – (x³ + 2x²y + 6xy² – y³)

= y³ – 3xy² – 4x²y – x³ – 2x²y – 6xy² + y³

= y³ + y³– 3xy²– 6xy²– 4x²y – 2x²y – x³

= 2y³– 9xy² – 6x²y – x³

Discussion