let F'(x) = f(x)∫(g(x),c) f(y) dy = F(g(x)) - F(c),上限=g(x) ,下限是常数(c)d/dx{∫(g(x),c) f(y) dx} = g'(x)F'(g(x)) = g'(x)f(g(x))下限是常数,可以直接求导积分下限是函数表达式时,变化为第一种形式∫(c,g(...