8.已知x2+y2+2x-6y+10=0,那么x,y的值分别为
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A.x=1,y=3 B.x=1,y=-3
C.x=-1,y=3 D.x=1,y=-3
9.把(m2+3m)4-8(m2+3m)2+16分解因式得
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A.(m+1)4(m+2)2 B.(m-1)2(m-2)2(m2+3m-2)
C.(m+4)2(m-1)2 D.(m+1)2(m+2)2(m2+3m-2)2
10.把x2-7x-60分解因式,得
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A.(x-10)(x+6) B.(x+5)(x-12)
C.(x+3)(x-20) D.(x-5)(x+12)
11.把3x2-2xy-8y2分解因式,得
A.(3x+4)(x-2) -4)(x+2)
C.(3x+4y)(x-2y) -4y)(x+2y)
12.把a2+8ab-33b2分解因式,得
A.(a+11)(a-3) -11b)(a-3b)
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B.(3x D.(3x[ ]
B.(a C.(a+11b)(a-3b) D.(a-11b)(a+3b)
13.把x4-3x2+2分解因式,得
A.(x2-2)(x2-1) -2)(x+1)(x-1)
C.(x2+2)(x2+1) +2)(x+1)(x-1)
14.多项式x2-ax-bx+ab可分解因式为
A.-(x+a)(x+b) a)(x+b)
C.(x-a)(x-b) +a)(x+b)
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B.(x2 D.(x2 ]
B.(x- D.(x[ [ 15.一个关于x的二次三项式,其x2项的系数是1,常数项是-12,且能分解因式,这样的二次三项式是
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A.x2-11x-12或x2+11x-12 B.x2-x-12或x2+x-12 C.x2-4x-12或x2+4x-12 D.以上都可以
16.下列各式x3-x2-x+1,x2+y-xy-x,x2-2x-y2+1,(x2+3x)2-(2x+1)2中,不含有(x-1)因式的有
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A.1个 B.2个
C.3个 D.4个
17.把9-x2+12xy-36y2分解因式为
A.(x-6y+3)(x-6x-3) B.-(x-6y+3)(x-6y-3) C.-(x-6y+3)(x+6y-3) D.-(x-6y+3)(x-6y+3) 18.下列因式分解错误的是
A.a2-bc+ac-ab=(a-b)(a+c) B.ab-5a+3b-15=(b-5)(a+3) C.x2+3xy-2x-6y=(x+3y)(x-2) D.x2-6xy-1+9y2=(x+3y+1)(x+3y-1)[ ]
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