Calculating Derivative of 1/(1-x) With a Ti89 Error?

Calculators
Thread starter Moose352
Start date Nov 7, 2004
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Derivative Error

In summary, the formula for calculating the derivative of 1/(1-x) is d/dx(1/(1-x)) = 1/(1-x)^2. To input this function into a Ti89 calculator, press the "Apps" button, select "Calculus Made Easy", and then select "Differentiate". Enter the function as "1/(1-x)" and press "Enter". If you encounter an error when trying to calculate the derivative, make sure the calculator is in "Exact" mode by pressing the "Mode" button and selecting "Exact/Approx" and then "Exact". This formula is only valid for values of x that are not equal to 1, as the function is undefined when x=1.

Nov 7, 2004

Moose352

Either I'm lost, or my Ti89 has an error in it's CAS (which is unbelievable). What is the derivative of 1/(1-x) ?

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Nov 7, 2004

jamesrc

Science Advisor

Gold Member

[tex]\frac 1 {(1-x)^2} [/tex]

What does your calculator say it is?

Nov 7, 2004

Moose352

Nevermind, i got it.

1. What is the formula for calculating the derivative of 1/(1-x)?

The formula for calculating the derivative of 1/(1-x) is d/dx(1/(1-x)) = 1/(1-x)^2.

2. How do I input this function into a Ti89 calculator?

To input this function into a Ti89 calculator, press the "Apps" button, select "Calculus Made Easy", and then select "Differentiate". Enter the function as "1/(1-x)" and press "Enter".

3. Why am I getting an error when trying to calculate the derivative?

This error can occur if the calculator is not in "Exact" mode. To fix this, press the "Mode" button, select "Exact/Approx", and then select "Exact".

4. Can I use this formula for any value of x?

No, this formula is only valid for values of x that are not equal to 1. When x=1, the function 1/(1-x) is undefined.

5. Can I use this formula to calculate higher order derivatives?

Yes, this formula can be used to calculate higher order derivatives by repeatedly applying the power rule. For example, the second derivative would be d/dx(1/(1-x)) = 2/(1-x)^3.