(3х-1)(4х+3)(3х-1)(2х-5)
=(3x-1)^2×(4x+3)×(2x-5)=(9x^2-6x+1)×(8x^2-20x+6x-15)=(9x^2-6x+1)×(8x^2-14x-15)=72x^4-174x^3-43x^2+76x-15