7/5-x/25=2(x+11)/50?
(2x-1)/(x-1)(x-2)=(x-5)/(x-2)(x-3) x/2x^2-11x-21=(x+7)/x^2-1
5x(x+7)(x+4)=5x(x^2+11X)
1x+2x+3x+4x+5x+6x+7x+8x+9x+10x+11x+12x+13x+14x+15x=550
x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?
(1)2x平方+3x=3,(2)x平方一2x+1=25(3)x(2x一5)=4x—10(4)x平方+5x+7=3x十11
(x+12)(x-2)+(x+7)(x+8)-(x+5)(x-10),其中x=2
2x+3x+4x+5x+x+6x+7x=100
已知2x*x+x-5=0,求代数式6x*x*x+7x*x-13x+11的值
X-5+8*X=7*X-2*X-1
x的平方-2x+1=15 ; x(2x-5)=4x-10 ; x的平方+5x+7=3x=11
计算:1/(x^2-7x+10)+1/(x^2-x-2)+1/(x^2+5x+4)+1/(x^2+11x+28)=( )
用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+.