888
Appendix A: Functions and Instructions
tCollect()
MATH\Algebra\Trig menu
tCollect(
expression1
)
⇒
⇒
⇒
⇒
expression
Returns an expression in which products and
integer powers of sines and cosines are converted
to a linear combination of sines and cosines of
multiple angles, angle sums, and angle
differences. The transformation converts
trigonometric polynomials into a linear
combination of their harmonics.
Sometimes
tCollect()
will accomplish your goals
when the default trigonometric simplification
does not.
tCollect()
tends to reverse
transformations done by
tExpand()
. Sometimes
applying
tExpand()
to a result from
tCollect()
,
or vice versa, in two separate steps simplifies an
expression.
tCollect((cos(
a
))^2)
¸
cos(2
ø
a
)
+
1
2
tCollect(sin(
a
)cos(
b
))
¸
sin(
a
ì
b
)+sin(
a
+
b
)
2
tExpand()
MATH\Algebra\Trig menu
tExpand(
expression1
)
⇒
⇒
⇒
⇒
expression
Returns an expression in which sines and cosines
of integer-multiple angles, angle sums, and angle
differences are expanded. Because of the identity
(sin(x))
2
+(cos(x))
2
=1, there are many possible
equivalent results. Consequently, a result might
differ from a result shown in other publications.
Sometimes
tExpand()
will accomplish your goals
when the default trigonometric simplification
does not.
tExpand()
tends to reverse
transformations done by
tCollect()
. Sometimes
applying
tCollect()
to a result from
tExpand()
,
or vice versa, in two separate steps simplifies an
expression.
Note:
Degree-mode scaling by
p
/180 interferes
with the ability of
tExpand()
to recognize
expandable forms. For best results,
tExpand()
should be used in Radian mode.
tExpand(sin(3
f
))
¸
4
ø
sin(
f
)
ø
(cos(
f
))
ñ ì
sin(
f
)
tExpand(cos(
a
ì
b
))
¸
cos(
a
)
ø
cos(
b
)+sin(
a
)
ø
sin(
b
)
Text
CATALOG
Text
promptString
Displays the character string
promptString
dialog
box.
If used as part of a
Dialog...EndDlog block
,
promptString
is displayed inside that dialog box. If
used as a standalone instruction,
Text
creates a
dialog box to display the string.
Text "Have a nice day."
¸
Done
Then
See
If,
page 828.
timeCnv()
CATALOG
timeCnv(
seconds
)
⇒
⇒
⇒
⇒
list
Converts seconds to units of time that can be
more easily understood for evaluation. The list is
in {
days,hours,minutes,seconds
} format.
Note:
See also
checkTmr()
and
startTmr()
.
timeCnv(152442117)
{1764 9 1 57}
Summary of Contents for Voyage 200
Page 36: ...Getting Started 36 D B D B Press Result ...
Page 45: ...Getting Started 45 3 0 D B D D B D Press Result ...
Page 46: ...Getting Started 46 D 2 0 0 2 D B Scroll down to October and press Press Result ...
Page 60: ...Getting Started 60 B D Press Result ...
Page 139: ...Previews 139 8 Complete the operation Press 2 d Steps and keystrokes Display 5 f 2 ...
Page 453: ...Differential Equation Graphing 453 ...
Page 468: ...Tables 468 ...
Page 777: ...Activities 777 ...
