Question

因式分解(7x^2+5x)/(x^+1) - 5x/(x^2-6)

Answer 1

原式=(7x^4-42x²+5x³-30x-5x³-5x)/(x²+1)(x²-6)

=(7x^4-42x²-35x)/(x²+1)(x²-6)

=7x(x³-6x-5)/(x²+1)(x²-6)

=7x(x³+x²-x²-6x-5)/(x²+1)(x²-6)

=7x[x²(x+1)-(x+1)(x-6)]/(x²+1)(x²-6)

=7x(x+1)(x²-x+6)/(x²+1)(x²-6)