1.原式=[(x+1)(3x-1)][(2x+1)(4x-1)]-36x^4 =(-1+2x+3x^2)(-1+2x+8x^2)-36x^4 =(-1+2x)^2+11x^2(-1+2x)+24x^4-36x^4 =(-1+2x)^2+11x^2(-1+2x)-12x^4 =(-1+2x+12x^2)(-1+2x-x^2) =-(12x^2+2x-1)(x-1)^2 2.令x=100,原式=根號((x-5)(x-1)(x+1)(x+5)+144) =根號((x^2-25)(x^2)+144) =根號(x^4-26x^2+169) =根號((x^2-13)^2) =x^2-13=10000-13=9987 |