化简:（x+y）+(2x+y/1*2)+(3x+y/2*3)+...+(9x+y/8*9)

化简:（x+y）+(2x+y/1*2)+(3x+y/2*3)+...+(9x+y/8*9)
化简:（x+y）+(2x+y/1*2)+(3x+y/2*3)+...+(9x+y/8*9)

化简:（x+y）+(2x+y/1*2)+(3x+y/2*3)+...+(9x+y/8*9)
原式=X+2X+……+9X+Y+Y/1×2+Y/2×3+……+Y/8×9
=（1+9）×9X÷2+Y+Y-1/2Y+1/2Y-1/3Y+……+1/8Y-1/9Y
=45X+17/9Y
当X=2 Y=9时原式=107

这个我也不太懂~~抱歉~~~