1.已知函数f(x)=|x|e~x,若函数y=f(x)+m只有一个零点,则实数m的取值范围是()A.(-1/e,0]B.(-∞,-1/e)∪{0}C.(-e,-1/e)D.(-∞,-1/e)∪(0,+∞)2.将函数f(x)=3~(1/2)sinπx/2图像上所有点向左平移1个单位长度,再把所得图像上各点的横坐标缩短为原来的1/2(纵坐标不变),得到函数g(x)的图像,则函数g(x)单调递增区间是____。3.已知数列{a_n}的各项均大于零,前n项和为 1. The function f (x) = | x | e ~ x is known. If the function y = f (x) + m has only one zero point, ] B (- ∞, -1 / e) ∪ {0} C. (-e, -1 / e) D. (- ∞, -1 / e) ∪ (0, + ∞) (x) = 3 ~ (1/2) sinπx / 2 All points on the image are shifted to the left by 1 unit length, and the abscissa of each point on the resulting image is reduced to 1/2 (the ordinate is not changed) Get the function g (x) of the image, then the function g (x) monotonically increasing interval is ____ 3. Known series {a_n} are greater than zero, the first n items and