1/(X+9)+1/(X+16)=1/X 求X的解连过程一起写出来,以前学的全忘没了,

问题描述:

1/(X+9)+1/(X+16)=1/X 求X的解
连过程一起写出来,以前学的全忘没了,

1/(X+9)+1/(X+16)=1/X
通分分母
=>(X+16)X/(X+9)(X+16)X+(X+9)X/(X+9)(X+16)X=(X+9)(X+16)/(X+9)(X+16)X
等号左右消分母
=>(X+16)X+(X+9)X=(X+9)(X+16)
=>XX+16X+XX+9X=XX+25X+144
=>XX=144
=>X=12或-12

1/(X+9)+1/(X+16)=1/X
(x+16+x+9)/[(x+16)(x+9)=1/x
x^2=16*9
x1=12,x2=-12

两边同乘x(x+9)(x+16)
变成x(x+16)+x(x+9)=(x+9)(x+16)
化简x2=9*16=144
所以x=±12
好好学习,天天向上吧~

方程两边同乘x(x+9)(x+16)
x(x+16)+x(x+9)=(x+9)(x+16)
x^2+16x+x^2+9x=x^2+16x+9x+144
x^2=144
x=±12
代回经检验,x=±12是方程的解

左右都乘以(x+9)(x+16)x
x(x+16)+x(x+9)=(x+9)(X+16)
x^2+16x+x^2+9x=X^2+25x+144
x^2=144
x=12或x=-12

[(X+9)+(X+16)]/(X+9)(X+16)=1/X
2X^2+25X=X^2+144
X^2=144
X=±12

方程两边同时乘以x(x+9)(x+16).......
则方程变形为x(x+16)+x(x+9)=(x+9)(x+16)
化简整理得 x的平方=144
x=12或者-12而且此时原方程的分母都不为零 都是方程的解

1/(X+9)+1/(X+16)=1/X
通分
(X+9)+(X+16)/(X+9)(X+16)=1/X
(2X+25)/(X+9)(X+16)=1/X
交叉相乘
(2X+25)x=(X+9)(X+16)
2X^2+25x=x^2+16x+9x+144
x^2=144
解得:x=12或x=-12

=> x(x+16)+x(x+9)=(16+x)(x+9)
=> 2x^2+25x=x^2+25x+144
=> x^2=144
=> x=12或x=-12

x^2+16x+x^2+9x=X^2+25x+144
x^2=144
x=12或x=-12

前两个通分(2x+25)/[(x+9)(x+16)]=1/x,然后化简2(x*x)+25x=(x*x)+25x+144,x=+_12