标题: 求助求助 [打印本页] 作者: 我要吃sumei 时间: 2011-11-11 21:39 标题: 求助求助 Determine the general equation of the secant from any point (A, f(A)) to the point on f(x)=4x where x=2. Describe how you would use this to find the equation of the tangent at the point (2, f(2)).