simplify 3/5x-2/7x,then solve the equation 3/5x-2/7x=2/5

英语翻译Find the sum of the roots of the equation:2x^3+8x^2-7x^5 1.Express the equation x^3+6*x^2-4*x+5=0 in reduced form and Express the equation x^3+6*x^2-4*x+5=0 in reduced form and d 英文的导数题Let f(x)=8x+20/(x^2).Then the equation of the tangent A function is defined by th equation d(x)=5(x-3)^2+1 x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少? 并化解该式至最简(simplify the expression),并列明过程.1) 15x ÷ 3 ÷ 5x -3 t 2x+3x+4x+5x+x+6x+7x=100 |X-1|+|X-2|+|X-3|+|X-4|+|X-5|+|X-6|+|X-7|+|X-8|+|X-9|+|X-10| Express the roots of the equation 3x^2 = -2 (x+3) in a+bi fo (2x-1)/(x-1)(x-2)=(x-5)/(x-2)(x-3) x/2x^2-11x-21=(x+7)/x^2-1 已知1+x+x^2+x^3=0,求x+x^2+x^3+x^4+x^5+x^6+x^7+x^8的值