下列分解因式正确的是( )A.2x2-xy-x=2x(x-y-1)B.-x2+2xy-3y=-y(xy-2x-3)C.x(x-y)-y(x-y)=(x-y)2
题型:单选题难度:简单来源:不详
下列分解因式正确的是( )A.2x2-xy-x=2x(x-y-1) | B.-x2+2xy-3y=-y(xy-2x-3) | C.x(x-y)-y(x-y)=(x-y)2 | D.x2-x-3=x(x-1)-3 |
|
答案
A、2x2-xy-x=x(2x-y-1),故此选项错误; B、-x2+2xy-3y,无法因式分解,故此选项错误; C、x(x-y)-y(x-y)=(x-y)2,故此选项正确; D、x2-x-3无法因式分解,故此选项错误; 故选:C. |
举一反三
把下列各式因式分解: (1)3x-12x3 (2)-2a3+12a2-18a (3)9a2(x-y)+4b2(y-x) (4)(x+y)2+2(x+y)+1. |
已知:x+y=1,xy=-3,求下列各式的值: (1)x2+y2; (2)x3+y3; (3)x5y+xy5. |
下列因式分解错误的是( )A.x2+xy=x(x+y) | B.x2-y2=(x+y)(x-y) | C.x2+6x+9=(x+3)2 | D.x2+y2=(x+y)2 |
|
下列多项式中能用平方差公式因式分解的是( )A.a2+b2 | B.-x2+y2 | C.-m2-n2 | D.x-x2 |
|
最新试题
热门考点