Question

3x2+4xy-y2因式分解 有过程

Answer 1

3x²+4xy-y²因式分解 有过程
解：3x²+4xy-y²=3(x²+4xy/3)-y²=3[(x+2y/3)²-4y²/9]-y²=3(x+2y/3)²-4y²/3-y²
=[(√3)(x+2y/3)]²-[y√(7/3)]²=[(√3)(x+2y/3)+y√(7/3)][(√3)(x+2y/3)-y√(7/3)]
=(1/3)[(3x+2y)+(√7)y][(3x+2y)-(√7)y]=(1/3)[3x+(2+√7)y][3x+(2-√7)y]

Answer 2

=4X2+4XY-Y2-X2
=-（4X2-4XY+Y2+X2)
=-{(2X-Y)2+X2)}
=-(2X-Y+X)(2X-Y-X)
=-(3X-Y)(X-Y)
应该没错