How do you find the derivative without values for x

Tell me where the key (or Submenu TAB) is and I will tell you how to use it. Apparently you were living in TI Planet and now have moved to Casio Planet and you need to adjust to the jet lag brought about by the transition.

In Run>Mat press [SHIFT][ MODE] to enter the (Setup).. On the 5th line: Derivative set the selection to ON.
Press Menu then Graph. Enter a function, validate and press F6:Draw.
Once graph is draw press the F1:trace key. A CROSS appears on the graph indicating the default starting position. At the bottom of the screen you see X=, Y=, and dY/dX=
The last one is obviously the value of the derivative at the position of the cross. Move the cursor to another point to see the values X, Y, and dY/dX.
You can also enter a value of X to find Y and dY/dX. Make sure the X-value you enter is in the interval between Xmin and Xmax, the window limits.

The calculator can calculate numerical values of derivatives of functions (at a given point). It does not have a Computer Algebra System so what you want to do cannot be done. You should look for a Casio calculator with a CAS, such as the ClassPad, the FX_Algebra 2 or the FX 9860G. Sorry.

The TI-84 does not have a Computer Algebra System and therefore cannot perform this operation.

It can however find the value of a derivative at a single point on a function. Put the function into your Y= menu and graph it. Press 2nd and Trace to go to the calc menu and choose the "dy/dx" option. Type the x-value at which you want to evaluate the derivative and press enter.

Once the graph is drawn you can use the Calculate menu to find

• 1:value, the value of the function at a point
• 2:Zero, the coordinate of a point where the function vanishes (has value zero)
• 3:minimum, the location of a point where the function has a minimum
• 4:maximum
  
• 5:intersect , the value of the function when it crosses the y-axis (y-intercept)
• 6:dy/dx, the value of the derivative of the function at a point.
• 7: Integral (f(x),dx)

For most of the foregoing calculations, you need to supply the interval of x-values that is of interest to you.To move the cursor along the curve to set the left limit and right limit of the interval of interest, use the LeftArrow and RightArrow keys.

You cannot find the location of an inflexion point as this requires the knowledge of the 2nd derivative of the function, and this calculator calculates the first derivative only. However, there may be 3rd-party programs that handle this, on ticalc.org website. Use at your own risk and under your sole responsibility.

To access the seven menu options above, you press [2nd][TRACE] to open the (CALC) menu. Use the Down and Up Arrows to move cursor along the menu options.

Do you mean as in a linear equation? If so it is simple the slope of the equation. If you are referring to an exponential equation the derivative is always changing so no.

If the setting Derivative is ON, the value of the first derivative is evaluated at the point of the graph where the trace cursor happens to be.
When you hit trace, the cursor was displayed at the X-value of -4. If you want the value of the derivative at x=2, just move the cursor to x=2. Use the right arrow key. Once the cursor is at x=2, the first derivative of the function at x=2 will be displayed.

- Here is a screen capture with the example of the function y=2x^2-3. I drew the tangent at x=2. It may not always be possible to have the value calculated at a point of your choosing. this is due to the finite value of the increment in the drawing. You may have to play with the window settings.


As you can see the computed value of the derivative is correct but the y-value is not (due to the finite pitch)
In the next screen capture all values are correct using trace, but the tangent line at x=2 was drawn separately.

Hello,
nDeriv( is valid only for real variables.
The syntax is as follows:
nDeriv ( expression, variable, value, epsilon)

expression: the function the derivative of which you want to calculate
variable: the name of the variable in the expression above (usually x)
value: the numerical value of the e x where you evaluate the derivative
epsilon: the numerical value of the tolerance. Default is 1x10^(-3). But you can change it to a smaller value to obtain a more precise result.

To use default value of epsilon
nDeriv ( expression, variable, value)

To use a different epsilon, ex 1x10^(-4)
nDeriv ( expression, variable, value, 0.0001)

nDeriv( A^3 , A, 5., 0.0001) should give you 75

Hope it helps.

Hello,
The second derivative indicates the rate of variation of the first derivative. Each point where the second derivative vanishes (has value 0) is an inflexion point of the curve.


How about using you calculator to graph that function? that is how you learn things. It will be my pleasure to help you learn how to graph functions.

Hello,

I assume that by anti-derivative you mean the integral. I believe that you can only calculate definite integrals with this calculator. A definite integral requires that you specify the function e.g ln(x), the variable, x, the numerical value of the lower limit, 0.5 and the numerical value of the upper limit , say 2.
Try this: INT(sin(x),x, 0, pi/2)
This calculator can only give numerical values of definite integrals. If you want to perform symbolic calculations, you shoul look towards some other, more sophisticated Casios Casio ClassPad 330, or the TI Voyage200PLT, or the TI89Titanium. etc.

Hope it helps

Hello,
Let us start wih the derivatives. To obtain the values of derivatives at points on a graph, you must set Derivative to ON
Press [AC/On] to trun calculator on. If you do not see the icons press [MENU], with arrows select [RUN] and press[EXE] . The screen clears.
Press [SHIFT][SETUP ] . The first few options must be set as follows
Mode : : Comp
Function Type : Y=
Draw Type : PLot
Derivative : ON This is the one to make derivatives visible
Angle : Rad unles you have to use degrees.
Coord : on if you want the x,y coordinates to be displayed
Grid : Off
Axes : ON to display x and y axes
Press [EXE] to save options. You are taken to [Run] screen.
Press [Menu] Play with arrows to select [GRAPH] and press [EXE]

You see a list Y1=, Y2= and so on
On the line Y1=, enter [SIN] [X,Theta, T] .
If function is complicated you may have to enter parentheses sin(X). When you finish to enter the functions you want to draw, hit [F6:Draw]
The graphs are displayed.
Press [F1:Trace] The trace function allows you to move cursor along the curve, while it displays the coordinates of the cursor. And since you set Derivative to ON, the trace displays also the value of the derivative of the curve at the position of the cursor.

There are other intersting tools, under [Sketch] and [G-solve ] such as minimum, maximum, tangente, inverse of the function drawn, integral under the curve, intercepts with the coordinates axes, etc. I will not spoil your fun by giving you the plot of the movie.

Hope it helps.