初二数学分式通分题
答:1.2ab分之3c=3c/2ab=9bc^3/6ab^2c^2 3ac^2分之b=b/3ac^2=2b^3/6ab^2c^2 4b^2c分之2=1/2b^2c=3ac/6ab^2c^2 2.2x+2分之x+2=(x+2)/2(x+1)=2(x+2)(x-2)/4(x+1)(x-2)x^2-x-2分之x=x/(x+1)(x-2)=4x/4(x+1)(x-2)8-4x分之3=-3/4(x...
答:1.x-y/2(x+y)=(x-y)(x+y)/2(x+y)�0�5 xy/(x+y)�0�5=2xy/2(x+y)�0�5 2.2mn/4m�0�5-9=2mn/(2m-3)(2m+3) 2m-3/2m+3=(2m-3)�0�5/(2m-3)(2m+3)这么辛...
答:(7)∵x^2一9=(x+3)(ⅹ一3),2x+6=2(x+3),∴公分母是2(x+3)(x一3),∴2x/(x^2一9)=4x/2(ⅹ+3)(ⅹ一3),x/(2x+6)=x(x一3)=ⅹ(x一3)/2(ⅹ+3)(ⅹ一3)。(8)∵a^2+2a+1=(a+1)^2,a^2一1=(a+1)(a一1)∴公分母是(a+1)^2(a一1)∴(a一1)/(a...
答:方法如下图所示,请认真查看,祝学习愉快:
答:解答:(1)a-b/3a+3b ,a+b/5a-5b (a-b)/(3a+3b)=5(a-b)^2/[15(a+b)(a-b)](a+b)/(5a-5b)=3(a+b)^2/[15(a+b)(a-b)](2)m-n ,mn/n-m m-n=-(m-n)^2/(n-m)mn/(n-m)=mn/(n-m)
答:答:第一项中m²+2mn=(m+n)²-n²=(m+n+n)*(m+n-n)=(m+2n)*m,所以原式=n/2m-1/2*(m+2n)第二项中2n²-mn=n(2n-m),那么原式可以化为-1/n+2/(2n-m)同理第三项分母可以化成(m+2n)(m-2n),那么式子最终可以化成n/2*(m+2n)+n/2*(m-2n)...
答:先分解因式,找出最简公分母:2/x平方-6X+8,原式=2/ x²-6x+8=2/(x-2)(x-4),1/x平方+x-6 =1/ x²+x-6=1/(x-2)(x+3)3-x/12+x-x(2次方)= (x-3) /[(x+3)(x-4)],∴ 公分母是:(x-2)(x+3))(x-4),∴通分:2/x平方-6X+8=2(x+...
答:2. 通分:(1) 4y/(12x^2y),5x/(12x^2y); (2)(x-1)/[x(x-1)(x+1)] ,(x+1)/[(x(x+1)(x-1)] .3. 军训期间,小华打靶的成绩是m发9环和n发7环,请问,小华的平均成绩是每发多少环?16/(m+n)习题17.1 1. 用分式填空:(1) 小明t小时走了s千米的路,则他走...
答:x/x^2-y^2--->x/(x+y)(x-y)--->x(x+y)/(x+y)^2(x-y)2xy/(x+y)^2--->2xy(x-y)/(x+y)^2(x-y)化为:x(x+y)/(x+y)^2(x-y) 2xy(x-y)/(x+y)^2(x-y)
答:(1)x/3y与3x/2y² (2)x-y/2x+2y与xy/(x+y)²∵公分母为 6y² ∵公分母为2(x+y)²∴x/3y= 2xy/6y² ∴x-y/2x+2y=(x-y)(x+y)/2(x+y)²3x/2y²= 9/6y² xy/(x+y)²=2xy/2(x+y)²(3)2m...
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杜倩19471041728:
初二数学分式通分题 -
7359舌拜
: (1)x-y/2x+2y=(x-y)/2(x+y)=(x-y)(x+y)/2(x+y)^2 xy/(x+y)^2=2xy/2(x+y)^2(2)6c/a²b=18bc/3a^2b^2 c/3ab²=ac/3a^2b^2(3)x-y/2x+2y=(x-y)/2(x+y)=(x-y)(x+y)/2(x+y)^2 xy/(x+y)^2=2xy/2(x+y)^2(4)2mn/4m²-9=2mn/(2m+3)(2m-3) 2m-3/2m+3=(2m-3)^2/(2m+3)(2m-3)
杜倩19471041728:
初二分式通分题,急!谢 -
7359舌拜
: X²(X-Y)/X(X-Y)(X+Y) (X+Y)²/X(X-Y)(X+Y)3X+2Y/2(3X-2Y) 4/(3X-2Y)(3X+2Y) X+Z/(x+y)(y+z)(X+Z) X+Y/(x+y)(y+z)(X+Z) b²(1-X)/ab(x+1)(2-x)(1-X) -a²(X+1)/ab(x+1)(2-x)(1-X) 希望回答对你有帮助哦~~ 呵呵~~
杜倩19471041728:
初二数学分式的通分问题!!追加【【20分!!】】 -
7359舌拜
: (1) 1/a+1=(A-1)/(A方-1) 3/1-a=-(3A+3)/(A方-1) 5/a^2-1(2) a/a-b=[A(A+B)(A+B方]/[(A方-B方)(A+B方)] b/a^2-b^2=B(A+B方)/[(A方-B方)(A+B方)] c/a+b^2 =C(A方-B方)/[(A方-B方)(A+B方)](3) a/a^2-4=A(A-2)/[(A+2)(A-2)方] a-1/a-2=(A-1)(A方-4)/[(A+2)(A-2)方] a+2/a^2-4a+4 =(A+2)方/[(A+2)(A-2)方]
杜倩19471041728:
急求!初二两道通分分式计算题 -
7359舌拜
: a²-3a=a(a-3), a²-9=(a+3)(a-3) 所以通分分母是a(a+3)(a-3)2x-2=2(x-1),(x-1)²=(x-1)(x-1) 所以通分分母是2(x-1)(x-1) 若有疑问可以百度Hi聊、
杜倩19471041728:
初二的几道分式通分1.2ab分之3c,3ac^2分之b,4b^2c分之22.2x+2分之x+2,x^2 - x - 2分之x,8 - 4x分之33.5b^2c分之4a,10a^2b分之3c, - 2ac^2分之5b4.a^2+2a+1分之... -
7359舌拜
:[答案] 1.2ab分之3c=3c/2ab=9bc^3/6ab^2c^2 3ac^2分之b=b/3ac^2=2b^3/6ab^2c^2 4b^2c分之2=1/2b^2c=3ac/6ab^2c^2 2.2x+2分之x+2=(x+2)/2(x+1)=2(x+2)(x-2)/4(x+1)(x-2) x^2-x-2分之x=x/(x+1)(x-2)=4x/4(x+1)(x-2) 8-4x分之3=-3/4(x-2)=-3(x+2)/4(x+1)(x-2) 3.5b...
杜倩19471041728:
初二数学分式通分题
7359舌拜
: 1)12/m²-9 2/m 3 =12/m²-9 2(m-3)/(m 3)(m-3) =(12 2m-6)/m²-9 =2(m 3)/(m 3)(m-3) =2/(m-3) 2)1/(a b) ÷(1/a 1/b) =1/(a b)÷(a b)/ab =ab/(a b)² 3)( a²-4/ a²-4a 4 -1/a-2 ) ÷ a² a/a-2 =( (a 2)(a-2)/ (a-2)² -1/a-2 ) ÷ a(a 1)/a-2 =((a 2-1)/a-2) ÷ a(a 1)/a-2 =a 1/(a-2)*(a-2)/a(a 1) =a 望采纳
杜倩19471041728:
初二数学分式通分求帮忙!(1) a/2b²,1/ - 3a²,5/6abc (2)2/9 - 3a,a - 1/a² - 9 -
7359舌拜
:[答案] 解;公分母为6a²b²c.(1) a/2b²=a*3a²c/2b²*3a²c=3a³c/6a²b²c ; 1/-3a²=1*2b²c/-3a²*2b²c=2b²c/-6a²b²c;5/6abc=5*ab/6abc...
杜倩19471041728:
请教一道分式通分题 急!!!(初2的) -
7359舌拜
: m-n-m^2+n^2=(m-n)-(m^2-n^2)=(m-n)-(m+n)(m-n)=(m-n)(1-m-n)1-m^2-2mn-n^2=1-(m^2+2mn+n^2)=1-(m+n)^2=(1+m+n)(1-m-n) 所以最简公分母是(m-n)(1-m-n)(1+m+n) 所以 m/(m-n-m^2+n^2)=m(2+m+n)/[(m-n)(1-m-n)(1+m+n)] n/(1-m^2-2mn-n^2)=n(m-n)/[(m-n)(1-m-n)(1+m+n)]
杜倩19471041728:
一道初二分式通分题,急!在线等 -
7359舌拜
: 像5和7为分母的通分时各乘对方一样 N/M上下同时乘M+P,得 N(M+P)/M(M+P) (2N+Q)/(M+P)同时乘M,得 (2N+Q)M/M(M+P) 最后得(3NM+NP+QM)/(M²+MP)
杜倩19471041728:
初二数学分式练习题1/1*3+1/2*4+1/3*5+……+1/9*11=?求过程 -
7359舌拜
:[答案] 每个单独的加式可以看成是 1/[N*(N+2)] 可以拆开为1/2[1/N-1/(N+2)] 所以上式可以写为:1/2(1-1/3+1/2-1/4+1/3-1/5+……+1/8-1/10+1/9-1/11) 可以看到后面从1/3开始被减去的都可以消掉,直到1/10,所以为: 1/2(1+1/2-1/10-1/11)=36/55