last+origin18x立绘
@井汪319:1/x(x+3)+1/(x+3)(x+6)+...+1/(x+15)(x+18) - 作业帮
冀所18617258324…… [答案] 1/x(x+3)+1/(x+3)(x+6)+...+1/(x+15)(x+18) =1/3[1/x-1/(x+3)]+1/3[1/(x+3)-1/(x+5)]+……+1/3[1/(x+15)-1/(x+18)] =1/3[1/x-1/(x+3)+1/(x+3)-1/(x+5)+……+1/(x+15)-1/(x+18)] =1/3[1/x-1/(x+18)] =1/3[(x+18)/x(x+18)-x/x(x+18)] =1/3[18/x(x+18)] =6/x(x+18)
@井汪319:6x+4(18 - x)=92怎么解方程 - 作业帮
冀所18617258324…… [答案] 去括号:6X+72-4X=92 移项:2X=20 X=10
@井汪319:15(x+2)=18(x - 2)怎么解 - 作业帮
冀所18617258324…… [答案] 15(x+2)=18(x-2) 15x+30=18x-36 -3x=-66 x=22
@井汪319:abcd均为有理数现规定一种新运算:|abcd|=ad - bc 那么当|2x+3 4 1 - x 5丨=18时 x= - 作业帮
冀所18617258324…… [答案] 代入数据即可: |2x+3 4 1-x 5丨=18 5(2x+3)-4(1-x)=18 10x+15-4+4x=18 14x+11=18 14x=7 x = 0.5 所以填0.5
@井汪319:13(x+18)=377的方程怎么解 - 作业帮
冀所18617258324…… [答案] 13(x+18)=377 x+18=29 x=11
@井汪319:18(x+0.9)=22.5, - 作业帮
冀所18617258324…… [答案] x+0.9 =22.5/18 x +0.9 =1.25 x = 1.25 -0.9 x =0.35
@井汪319:已知int i=0,k=18, x=5,y=0;表达式 i=(x - = ++x),(x+=y,y+=6)...
冀所18617258324…… [答案] 2/x+3+2/3-x+2x+18/x^2-9 =[2(X-3)-2(X+3)+2X+18]/(X+3)(X-3) =2(X+3)/(X+3)(X-3) =2/(X-3) ∴X-3=±1,±2 ∴X=4,2,5,1 符合条件x的值的和为4+2+5+1=12
@井汪319:10X+20(18 - X)=280解一下方程要过程 - 作业帮
冀所18617258324…… [答案] 10x+360-20x=280 80=10x x=8 手机打得,很累的,给点分吧!
@井汪319:如果(2x - 18)(x+p)的乘积中不含x项,则p等于多少? - 作业帮
冀所18617258324…… [答案] (2x-18)(x+p) =2x^2+2px-18x-18p =2x^2+(2p-18)x-18p 积中不含x项 则2p-18=0 即p=9
冀所18617258324…… [答案] 1/x(x+3)+1/(x+3)(x+6)+...+1/(x+15)(x+18) =1/3[1/x-1/(x+3)]+1/3[1/(x+3)-1/(x+5)]+……+1/3[1/(x+15)-1/(x+18)] =1/3[1/x-1/(x+3)+1/(x+3)-1/(x+5)+……+1/(x+15)-1/(x+18)] =1/3[1/x-1/(x+18)] =1/3[(x+18)/x(x+18)-x/x(x+18)] =1/3[18/x(x+18)] =6/x(x+18)
@井汪319:6x+4(18 - x)=92怎么解方程 - 作业帮
冀所18617258324…… [答案] 去括号:6X+72-4X=92 移项:2X=20 X=10
@井汪319:15(x+2)=18(x - 2)怎么解 - 作业帮
冀所18617258324…… [答案] 15(x+2)=18(x-2) 15x+30=18x-36 -3x=-66 x=22
@井汪319:abcd均为有理数现规定一种新运算:|abcd|=ad - bc 那么当|2x+3 4 1 - x 5丨=18时 x= - 作业帮
冀所18617258324…… [答案] 代入数据即可: |2x+3 4 1-x 5丨=18 5(2x+3)-4(1-x)=18 10x+15-4+4x=18 14x+11=18 14x=7 x = 0.5 所以填0.5
@井汪319:13(x+18)=377的方程怎么解 - 作业帮
冀所18617258324…… [答案] 13(x+18)=377 x+18=29 x=11
@井汪319:18(x+0.9)=22.5, - 作业帮
冀所18617258324…… [答案] x+0.9 =22.5/18 x +0.9 =1.25 x = 1.25 -0.9 x =0.35
@井汪319:已知int i=0,k=18, x=5,y=0;表达式 i=(x - = ++x),(x+=y,y+=6)...
冀所18617258324…… [答案] 2/x+3+2/3-x+2x+18/x^2-9 =[2(X-3)-2(X+3)+2X+18]/(X+3)(X-3) =2(X+3)/(X+3)(X-3) =2/(X-3) ∴X-3=±1,±2 ∴X=4,2,5,1 符合条件x的值的和为4+2+5+1=12
@井汪319:10X+20(18 - X)=280解一下方程要过程 - 作业帮
冀所18617258324…… [答案] 10x+360-20x=280 80=10x x=8 手机打得,很累的,给点分吧!
@井汪319:如果(2x - 18)(x+p)的乘积中不含x项,则p等于多少? - 作业帮
冀所18617258324…… [答案] (2x-18)(x+p) =2x^2+2px-18x-18p =2x^2+(2p-18)x-18p 积中不含x项 则2p-18=0 即p=9