因式分解 ① x(b+c-d)-y(d-b-c)-z(c+b-d) ②（a-b)^2-2(a-b)(a+b)+(a+b)

来源：学生作业帮编辑：搜搜做题作业网作业帮分类：数学作业时间：2024/06/28 12:50:30

因式分解 ① x(b+c-d)-y(d-b-c)-z(c+b-d) ②（a-b)^2-2(a-b)(a+b)+(a+b)^2 ③4(5a-b)^2-9(2a+3b)^2

① x(b+c-d)-y(d-b-c)-z(c+b-d)
=xb+xc-xd-yd+yb+yc-zc-zb+zd
=b(x+y-z)+c(x+y-z)-d(x+y-z)
=(x+y-z)(b+c-d)
②（a-b)²-2(a-b)(a+b)+(a+b)²
=[（a-b）-（a+b）]²
=（-2b）²
=4b²
③ 4(5a-b)²-9(2a+3b)²
=[2*（5a-b）]²-[3*（2a+3b）]²
=（10a-2b）²-（6a+9b）²
=[（10a-2b）+(6a+9b)][(10a-2b)-(6a+9b)]
=(16a+7b)(4a-11b)

[a,b)×[c,d a,b ,c ,d 第一类：A B C D.X Y Z; a,b,c,d>0 证(a/(b+2c+3d))+(b/(c+2d+3a))+(c/d+2a+3b))+(d/(a+2b b/a(a+b)+c/(a+b)(a+b+c)+d/(a+b+c)(a+b+c+d) 已知a/b=c/d,求证a+2b/b=c+2d/d 求行列式 |a+b+c+2d a b c,d b+c+d+2a b c,d a a+c+d+2b c,d a b a+b ( )-(c-d)=(a-c)-(-b+d) A B C D × 9 ___________________ D C B A (1) A = ( )(2) B = ( 分解因式(a-b)(c+d)-(a-b)(c-d) 已知a>b,c>d,求证a+c>b+d. a b c d* d_________=d c b a