先化简在求值8x³(x-3)+12x²(3-x),其中x=3/2
问题描述:
先化简在求值8x³(x-3)+12x²(3-x),其中x=3/2
答
8x³(x-3)+12x²(3-x)
=-8x³(x-3)+12x²(3-x)
=(3-x)(12x^2-8x^3)
=(3-x)*4x^2(3-2x)
=(3-3/2)*4(3/2)^2*(3-2*3/2)
=0
答
8x³(x-3)+12x²(3-x),
=8x³(x-3)-12x²(x-3),
=4x²(x-3)(2x-3)
把x=3/2代入代数式得:
=4x²(x-3)(2*3/2-3)
=4x²(x-3)x0
=0
答
原式=8x³(x-3)-12x²(x-3)
=(x-3)(8x³-12x²)
=x²(x-3)(8x-12)
=4x²(x-3)(2x-3)
将x=3/2带入
∴得
原式=4(3/2)²(3/2-3)(2*3/2-3)
=9*(-3/2)*0
=0
答
原式=8x^4-24x³+36x²-12x³
=8x^4-36x²+36x²
=81/2-81/2+81
=81
答
8x³(x-3)+12x²(3-x),
=8x³(x-3)-12x²(x-3),
=4x²(x-3)(2x-3)
=4x²(x-3)(2*3/2-3)
=4x²(x-3)x0
=0
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