学习必备欢迎下载A DERIV ATIVE FUNCTION 1
The derivative function or simply the derivative is defined as )( xf= y =xxfxxfxyxx)()(limlim002
Find the derivative function a) Find y, b) Find the average rate of change xy , c) Find the limit xyx0lim
Geometric significance Consider a general function y=f(x), a fixed point A(a,f(a)) and a variable point B(x,f(x))
The slope of chord AB=axafxf)()(
Now as BA, xa and the slope of chord ABslope of tangent at A
So, axafxfax)()(limis )(af
Thus, we can know the derivative at x=a is the slope of the tangent at x=a
Rules )( xf)( xfC(a constant) 0 nx1nnxxsinxcosxcosxsinxtanxx22cos1secxarcsin2-11x学习必备欢迎下载xlnx1xalogexalog1xexexaaax ln)()(xvxu)()(xvxu)()(xvxu)()()()(xvxuxvxu)()(xvxu2vvuvu)0(v5
The chain rule If )(ufywhere )(xuuthen dxdududydxdy
)()(xgexf)()