How to take the derivative of this function

In summary, the limit as x approaches 0 of (1+sin(pi*x))^(1/x) is equal to e^(pi). To find this limit, you can use the fact that sin(pi*x) is approximately pi*x as x approaches 0, and take the logarithm of the expression to simplify the calculation.
  • #1
JKLM
21
0
What is the Lim as x approaches 0 of (1+sin(pi*x))^(1/x)
I couldn't figure out how to take the derivative of this function
 
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  • #2
You don't need to take derivatives.

As x->0, sin(pi*x) is approx pi*x. Your expression can be represented as exp(ln(1+pi*x)/x). Then ln(1+pi*x) is approx pi*x as x->0. The net result is exp(pi) is the limit that you want.
 
  • #3
for the derivative part take log
say
[tex]L = \lim_{x\rightarrow 0}[1+sin(\pi x)]^\frac{1}{x}[/tex]

Take log
[tex]logL = \lim_{x\rightarrow 0}\frac{log(1+sin\pi x)}{x}[/tex]
I hope u can differentiate from there on

Though mathman's reply is best u should do it that way
 

1. How do I take the derivative of a simple polynomial function?

To take the derivative of a simple polynomial function, you can use the power rule. First, bring down the exponent and multiply it by the coefficient. Then, subtract 1 from the exponent. This will give you the derivative of the function.

2. What is the chain rule and when do I use it?

The chain rule is a method for taking the derivative of composite functions. It is used when the function contains nested functions, such as f(g(x)). To use the chain rule, you need to find the derivative of the outer function and the derivative of the inner function, and then multiply them together.

3. How do I take the derivative of a trigonometric function?

To take the derivative of a trigonometric function, you can use the trigonometric identities and the chain rule. For example, the derivative of sin(x) is cos(x), and the derivative of cos(x) is -sin(x). If the function is more complicated, you may need to use the chain rule to find the derivative.

4. Can I use the quotient rule to take the derivative of any function?

No, the quotient rule can only be used for functions that are in the form of f(x)/g(x). If the function is not in this form, you will need to manipulate it algebraically to get it into this form before using the quotient rule.

5. How do I take the derivative of a logarithmic or exponential function?

To take the derivative of a logarithmic or exponential function, you can use the logarithmic differentiation method. This involves taking the natural logarithm of both sides of the function and then using the power rule and chain rule to find the derivative. The final step is to take the exponential of both sides to get the original function's derivative.

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