The
differentiate
command is on the Calc menu and also available directly from the keyboard:
2nd
8. (The letter d is not the same thing.)
It computes derivatives.
To get the second derivative, enter d (x^5,x,2).
d (x^5,x,-1)
gives an antiderivative.
To evaluate a derivative at a number, use the with
bar.
Even if there's only one variable visible, you have to tell the calculator
what variable you're differentiating with respect to.
The
integrate
command is on the Calc menu and also available directly from the keyboard:
2nd
7.
It computes integrals and antiderivatives. The first picture is with Pretty
Print OFF, to show the syntax.
Even if there's only one variable visible, you have to tell the calculator
what variable you're integrating with respect to.
The
limit
command computes limits.
For limits at infinity, you need the infinity
key. You can also specify positive infinity or negative infinity by adding
the + and (-) keys.
Adding a third comma followed by any negative number asks for a limit from
the left.
Adding a third comma followed by any positive number asks for a limit from
the right.
Even if there's only one variable visible, you have to tell the calculator
what variable you're taking a limit with respect to.
The
sum
command adds up a finite or (sometimes) infinite number of terms. You have
to supply a formula.
You may use any variable you like; n is just traditional.
You can find the infinity key on the keyboard.
Even if there's only one variable visible, you have to tell the calculator
what variable you're summing with respect to.
The
product
command multiplies a finite or (sometimes) an infinite number of terms.
You have to supply a formula.
fMin
and fMax give the input values which produce the smallest outputs
and largest outputs from a function or expression.
You don't
need the capital M's if you type in the commands.
To restrict the allowed inputs, use the with
bar.
(Click here for information about the less than
or equal to and the and.)
Even if there's only one variable visible, you have to tell the calculator
what the input variable is.
The
arcLen
command computes the length of the graph of the given expression between
the inputs given.
You don't
need the capital L if you type in the command.
Even if there's only one variable visible, you have to tell the calculator
what the input variable is.
Unfortunately, this command doesn't work with curves defined parametrically.
For that you have to figure out (or remember) the integral that gives the
right result.
The
taylor
command computes Taylor polynomials.
The syntax is taylor(function,variable,degree[,optional center]).
You need to provide a formula for the function, which means the calculator
can compute values of the function (almost) exactly.
Which means a Taylor polynomial approximation has only theoretical value.
But you might want to know one anyway.
Even if there's only one variable visible, you have to tell the calculator
what the input variable is.
The
nDeriv
command computes derivatives numerically.
You don't
need the capital D if you type in the command.
The formula that gives nDeriv(f(x),x) is (f(x+h) - f(x-h))/2h.
h is 0.001 unless you supply a different value.
To evaluate the numerical derivative at a number, use the with
bar.
It's not clear why you would want a numerical derivative when you can get
an exact derivative.
Even if there's only one variable visible, you have to tell the calculator
what variable you're differentiating with respect to.
The
nInt
command computes integrals numerically.
You don't
need the capital I if you type in the command.
This accomplishes the same thing as ordinary integration
in APPROXIMATE mode.
Even if there's only one variable visible, you have to tell the calculator
what variable you're integrating with respect to.
The
deSolve
command solves differential equations symbolically.
You don't
need the capital S if you type in the command.
The derivative symbol (') is on the keyboard: 2nd B on the
TI-92+ and 2nd = on the TI-89.
Use it twice for second derivatives. The calculator can't solve differential
equations with third or higher derivatives.
You have to tell the calculator both the input variable and the output
variable.
The @1 symbol stands for an arbitrary constant.
The second example has no arbitrary constant because we supplied an initial
condition.
(It's a mystery why the calculator chose to factor out an e-t.)
(It's another mystery what happened to @2 and @3 on this screen.)