因式分解 x³-9x²y+26xy²-24y³?

因式分解 x³-9x²y+26xy²-24y³?
因式分解 x³-9x²y+26xy²-24y³?

因式分解 x³-9x²y+26xy²-24y³?
x³-9x²y+26xy²-24y³
= x³-9x²y+20xy² +6xy²-24y³
= x(x²-9xy+20y²) +6y²(x-4y)
= x(x-4y)(x-5y) +6y²(x-4y)
= (x-4y)(x²-4xy+6y²)

原式
= x³-9x²y+20xy² +6xy²-24y³
= x(x²-9xy+20y²) +6y²(x-4y)
= x(x-4y)(x-5y) +6y²(x-4y)
= (x-4y)(x²-5xy +6y²)
= (x-4y)(x-2y)(x-3y)