3x(x-1)-(3x^4-2x^3)除以(-1/2x)^2,其中x=根号3先化简,再求值
问题描述：
3x(x-1)-(3x^4-2x^3)除以(-1/2x)^2,其中x=根号3
先化简,再求值
答
3x(x-1)-(3x^4-2x^3)/(-1/2x)^2
=3x^2-3x-(12x^2-8x)
=-9x^2+5x,
当x=√3时,
原式=-9x^2+5x
=-9*(√3)^2+5√3,
=5√3-81.
答
3x(x-1)-(3x^4-2x^3)
=3x^2-3x-3x^4+2x^3
所以3x(x-1)-(3x^4-2x^3)除以(-1/2x)^2
=(3x^2-3x-3x^4+2x^3)/[x^2/4]
=3x^2/[x^2/4]-3x/[x^2/4]-3x^4/[x^2/4]+2x^3/[x^2/4]
=12-12/x-12x^2+8x
=12-12/√3-12*3+8√3
=-24-4√3+8√3
=4√3-24