f(x) = √(x+1) - √(1-x)根号下无负数：x+1≥0,并且1-x≥0,所以定义域 -1 ≤x ≤1在定义域内x+1单调增；√(x+1)单调增；1-x单调减,√(1-x)单调减,- √(1-x)单调增单调增+单调增=单调增∴f(x) = √(x+1) - √(1-x)单...