87年大兴安岭火灾费翔:因式分解

来源:百度文库 编辑:查人人中国名人网 时间:2024/04/28 01:54:14
(ax+bx)^2+(bx-ax)^2
打错了(ax+by)^2+(bx-ay)^2

(ax)^2+2axbx+(bx)^2+(bx)^2-2axbx+(ax)^2
=2(ax)^2+2(bx)^2
=2[(ax)^2+(bx)^2]
=2x^2(a^2+b^2)

(ax+bx)^2+(bx-ax)^2
=a^2x^2+b^2x^2+2abx^2+b^2x^2+a^2x^2-2abx^2
=2a^2x^2+2b^2x^2
=2x^2(a^2+b^2)

(ax+bx)^2+(bx-ax)^2

=x^2[(a+b)^2+(b-a)^2]
=2x^2[b^2+a^2]

(ax+by)^2+(bx-ay)^2
=(ax)^2+2axby+(by)^2+(bx)^2-2aybx+(ay)^2
=(ax)^2+(ay)^2+(by)^2+(bx)^2
=a^2(x^2+y^2)+b^2(x^2+y^2)
=(a^2+b^2)(x^2+y^2)