化简 求计算或化简(2+3x)/(4-9x)-(1+3x)/(2-3x)-2/(3x-2)

求计算或化简(2+3x)/(4-9x)-(1+3x)/(2-3x)-2/(3x-2)  

求计算或化简(2+3x)/(4-9x)-(1+3x)/(2-3x)-2/(3x-2)

(2+3x)/(4-9x)-(1+3x)/(2-3x)-2/(3x-2)
=(2+3x)/[(2+3x)(2-3x)]-(1+3x)/(2-3x)-[-2/(2-3x)]
=1/(2-3x)-(1+3x)/(2-3x)+2/(2-3x)
=[1-(1+3x)+2]/(2-3x)
=(2-3x)/(2-3x)
=1

(2+3x/4-9x^2)-(1+3x/2-3x)-(2/3x-2)

原式=-(2+3x)/(3x+2)(3x-2)+(1+3x)/(3x-2)-2/(3x-2)
=-1/(3x-2)+(1+3x)/(3x-2)-2/(3x-2)
=(-1+1+3x-2)/(3x-2)
=(3x-2)/(3x-2)
=1

计算：2+3x/4-9x^2-1+3x/2-3x-2/3x-2 急用

解：(2+3x)/(4-9x^2)-(1+3x)/(2-3x)-2/(3x-2 )
=(2+3x)/[(2+3x)(2-3x)]-(1+3x)/(2-3x)+2/(2-3x )
=1/(2-3x)+(2-1-3x)/(2-3x)
=1/(2-3x)+(1-3x)/(2-3x)
=(2-3x)/(2-3x)=1

计算：2+3x/4-9x^2-1+3x/2-3x-2/3x-2 要过程

解：
2+3x/4-9x^2-1+3x/2-3x-2/3x-2
=2+(3x/4)-9x^2-1+(3x/2)-3x-(2/3)x-2
=2-1-2+(3x/4)+(3x/2)-(2x/3)-9x^2
=-1+(3/4+3/2-2/3)x-9x^2
=-1+(9/12+18/12-8/12)-9x^2
=-1+19x/12-9x^2
=-9x^2+19x/12-1

计算:2+3x/4-9x^2-1+3x/2-3x-2/3x-2 急用 谢谢

2+3x/4-9x^2-1+3x/2-3x-2/3x-2=-9x^2+17x/12-1

4-9x的平方分之2+3x - 2-3x分之1+3x - 3x-2分之2 通分

4-9x的平方分之2+3x - 2-3x分之1+3x - 3x-2分之2
=(2+3x)/(2+3x)(2-3x)-(1+3x)/(2-3x)+2/(2-3x)
=(1-1-3x+2)/(2-3x)
=(2-3x)/(2-3x)
=1

(3x-1/2)(-1/2-3x)(-1/4-9x的平方)

原式=(-1/2+3x)(-1/2-3x)(-1/4-9x²)
=(1/4-9x²)(-1/4-9x²)
=81x^4-1/16

先化简再求值【 [x^2-9] / [ x^2+6x+9]】 ×【[3x^3+9x^2] / [x^2-3x]】

[x^2-9] / [ x^2+6x+9]】 ×【[3x^3+9x^2] / [x^2-3x]】
=(x+3)(x-3)/(x+3)²*(3x²(x+3)/x(x-3))
=(x-3)/(x+3)*3x(x+3)/(x-3)
=3x;
【 [x+y] / [ x^4+y^4]】 ÷【1 / [x^2+y^2]】
=(x+y)(x²+y²)/(x^4+y^4)

7-9x/2-3x -4x-5/2-3x =1 x=?

(7-9x)/(2-3x) -(4x-5)/(2-3x) =1
[(7-9x) -(4x-5)]/(2-3x) =1
(7-9x -4x+5)/(2-3x) =1
(12-13x)/(2-3x) =1
(12-13x)/(2-3x) -1=0
[(12-13x)-(2-3x) ]/(2-3x) =0
(12-13x-2+3x)/(2-3x) =0
(10-10x)/(2-3x) =0
10(1-x)/(2-3x) =0
(1-x)/(2-3x) =0
1-x=0
x=1
经检验x=1是方程的解

先化简再求值3x[a^2-3x(a-3x)]+a(9x^2-3ax+a),其中x=-1/3,a=-1/2

3x[a^2-3x(a-3x)]+a(9x^2-3ax+a),
=3x(a^2-3ax+9x^2)+a(9x^2-3ax+a),
=3a^2x-9ax^2+27x^3+9ax^2-3a^2x+a^2
=27x^3+a^2
=27*(-1/3)^3+(-1/2)^3
=27*(-1/27)-1/8
=-1-1/8
=-9/8