Function X is a variable...
Date: 9 Jan 1995 11:01:59 -0500 From: Winnie Fan Subject: question Hello Dr. Math, I am a student in calculus at Monta Vista High School. Right now we are learning general exponential and logarithmic functions. In class we are giving the formula Dx a^u = a^u ln a * Dx u. With this formula, I am able to do problems where a is a number. In one of my homework problems, we are giving the function f(x) = X^tanX. Then we are asked to find the derivative of the function f(x). Since in this function X is a variable, I am stuck here. Please help! Winnie Fan
Date: 9 Jan 1995 12:46:25 -0500 From: Dr. Ken Subject: Re: question Hello there! You're right, this is a different kind of problem, but you can turn it into a very similar problem by writing the function in a different form. Try this: x^Tan[x] = e^Ln[x^Tan[x]] = e^(Tan[x] * Ln[x]) And then see if you can handle it from there. This is the standard way of dealing with nasty exponents: get them in terms of a constant base. -Ken "Dr." Math
Search the Dr. Math Library:
Ask Dr. MathTM
© 1994-2013 The Math Forum