Wednesday

July 23, 2014

July 23, 2014

Posted by **Anonymous** on Monday, October 29, 2007 at 2:53pm.

a) Determine f*(x) for f(x) = cosx

b) write an equation that expresses the relationship between the functions f* and f` where f` denotes the usual derivative of f

- calculus -
**drwls**, Monday, October 29, 2007 at 3:20pmUse the trigonometric identity

cos (x + h) = cosx cosh - sinx sinh

This means that

cos(x + h) - cosx

= (cosh -1) cosx - sin x sinh

For very small h, sin h = h and cos h = 1, so [cos(x + h) - cosx]/h -> -sin x

-sin x is the exact derivative of cos x.

**Related Questions**

calculus - f*(x) = lim as h -> 0 [f(x+h)-f(x-h)]/ h write an equation that ...

Calculus..more help! - I have a question relating to limits that I solved lim(x...

calculus - State which of the conditions are applicable to the graph of y = f(x...

Calculus - Find the following limits algebraically or explain why they don’t ...

Calculus - 1. a) For the Function and point below , Find f’(a). b) Determine ...

Calculus - 1. a) For the Function and point below , Find f’(a). b) Determine ...

Calculus - Give an appropriate answer. Let lim x→6 f(x)=81. Find lim x&#...

CALCULUS - need help! - Determine the limit of the trigonometric function (if it...

Calculus - (a) By graphing the function f(x) = (cos 2x − cos x)/x2 and ...

Calculus - (a) By graphing the function f(x) = (cos 2x − cos x)/x2 and ...