解由-x^2+2x+3≥0即x^2-2x-3≤0即(x-3)(x+1)≤0解得-1≤x≤3故函数的定义域为[-1,3]又由y=√-x^2+2x+3=√-(x-1)^2+4故内函数U=-(x-1)^2+4在[-1,1]是增函数,在[1,3]是减函数而y=√U是增函数故函数y=根号-x^2+2x+3的单...
