Tangent Line

[naoufelabs]

Hi everyone,

Please I have a problem to find a slope (Tangent line) of any linear function without using (x2-x1; y2-y1).
What I want is a function that can be applied in any position of any type of function, example: x2, 3x3+sin(x), ln(x)+x3, and so one. (Like as in this web page "Java Applet" : http://www.math.brown.edu/help/tangentline.html)

Thank you.

[Mark44]

Hi everyone,

Please I have a problem to find a slope (Tangent line) of any linear function without using (x2-x1; y2-y1).
What I want is a function that can be applied in any position of any type of function, example: x2, 3x3+sin(x), ln(x)+x3, and so one. (Like as in this web page "Java Applet" : http://www.math.brown.edu/help/tangentline.html)

Thank you.

Is this a homework problem?

What you are asking is unclear. A linear function is one with the form f(x) = ax + b. This function's graph is a straight line with slope a.

For other functions, such as the ones you mentioned, the slope of the tangent line at a point on the curve, is given by the derivative of the function, evaluated at the x value at the point in question.

So are you asking about linear functions or functions in general?

[naoufelabs]

I ask about linear function.

[HallsofIvy]

Any linear function of x can be written as y= ax+ b for some numbers a and b. The slope is the number a.

[naoufelabs]

Thanks