Texas Instruments TI-82 User Manual - Page 67

Defining Functions in the Y= List

Page 67 highlights

Defining Functions in the Y= List Pressing o accesses the Y= edit screen, where you enter the functions to graph. You can store up to ten functions in memory at one time. You can graph one or more of these functions at a time. Displaying the Functions in the Y= List Press o to display the Y= edit screen. In the example below, the Y1 and Y2 functions are defined. Defining a New Function To define a new function, enter an expression on the Y= edit screen. 1. Move the cursor to the function in the Y= list you want to define. If necessary, press ' to erase a previously entered function. 2. Enter the expression to define the function. ¦ You may use functions and variables (including matrices and lists) in the expression. If the expression evaluates to a value that is not a real number, that point is not plotted; an error does not occur. ¦ The independent variable in the function is X. You may press „, rather than pressing ƒ ãXä, for the X variable. (Func MODE defines the independent variable as X.) ¦ The expression is stored as one of the ten user-defined functions in the Y= list as you enter it. 3. When you complete the expression, press Í to move to the beginning of the next function. Function Graphing 3-5

  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
  • 10
  • 11
  • 12
  • 13
  • 14
  • 15
  • 16
  • 17
  • 18
  • 19
  • 20
  • 21
  • 22
  • 23
  • 24
  • 25
  • 26
  • 27
  • 28
  • 29
  • 30
  • 31
  • 32
  • 33
  • 34
  • 35
  • 36
  • 37
  • 38
  • 39
  • 40
  • 41
  • 42
  • 43
  • 44
  • 45
  • 46
  • 47
  • 48
  • 49
  • 50
  • 51
  • 52
  • 53
  • 54
  • 55
  • 56
  • 57
  • 58
  • 59
  • 60
  • 61
  • 62
  • 63
  • 64
  • 65
  • 66
  • 67
  • 68
  • 69
  • 70
  • 71
  • 72
  • 73
  • 74
  • 75
  • 76
  • 77
  • 78
  • 79
  • 80
  • 81
  • 82
  • 83
  • 84
  • 85
  • 86
  • 87
  • 88
  • 89
  • 90
  • 91
  • 92
  • 93
  • 94
  • 95
  • 96
  • 97
  • 98
  • 99
  • 100
  • 101
  • 102
  • 103
  • 104
  • 105
  • 106
  • 107
  • 108
  • 109
  • 110
  • 111
  • 112
  • 113
  • 114
  • 115
  • 116
  • 117
  • 118
  • 119
  • 120
  • 121
  • 122
  • 123
  • 124
  • 125
  • 126
  • 127
  • 128
  • 129
  • 130
  • 131
  • 132
  • 133
  • 134
  • 135
  • 136
  • 137
  • 138
  • 139
  • 140
  • 141
  • 142
  • 143
  • 144
  • 145
  • 146
  • 147
  • 148
  • 149
  • 150
  • 151
  • 152
  • 153
  • 154
  • 155
  • 156
  • 157
  • 158
  • 159
  • 160
  • 161
  • 162
  • 163
  • 164
  • 165
  • 166
  • 167
  • 168
  • 169
  • 170
  • 171
  • 172
  • 173
  • 174
  • 175
  • 176
  • 177
  • 178
  • 179
  • 180
  • 181
  • 182
  • 183
  • 184
  • 185
  • 186
  • 187
  • 188
  • 189
  • 190
  • 191
  • 192
  • 193
  • 194
  • 195
  • 196
  • 197
  • 198
  • 199
  • 200
  • 201
  • 202
  • 203
  • 204
  • 205
  • 206
  • 207
  • 208
  • 209
  • 210
  • 211
  • 212
  • 213
  • 214
  • 215
  • 216
  • 217
  • 218
  • 219
  • 220
  • 221
  • 222
  • 223
  • 224
  • 225
  • 226
  • 227
  • 228
  • 229
  • 230
  • 231
  • 232
  • 233
  • 234
  • 235
  • 236
  • 237
  • 238
  • 239
  • 240
  • 241
  • 242
  • 243
  • 244
  • 245
  • 246
  • 247
  • 248
  • 249
  • 250
  • 251
  • 252
  • 253
  • 254
  • 255
  • 256
  • 257
  • 258
  • 259
  • 260
  • 261
  • 262
  • 263
  • 264
  • 265
  • 266
  • 267
  • 268
  • 269
  • 270
  • 271
  • 272
  • 273
  • 274
  • 275
  • 276
  • 277
  • 278

Function Graphing
3-5
Defining Functions in the Y= List
Pressing
o
accesses the Y= edit screen, where you enter the functions to graph.
You can store up to ten functions in memory at one time. You can graph one or
more of these functions at a time.
Displaying the Functions in the Y= List
Press
o
to display the
Y=
edit screen. In the example below, the
Y
1
and
Y
2
functions are defined.
Defining a New Function
To define a new function, enter an expression on the
Y=
edit screen.
1.
Move the cursor to the function in the
Y=
list you want to define. If
necessary, press
to erase a previously entered function.
2.
Enter the expression to define the function.
¦
You may use functions and variables (including matrices and lists) in
the expression. If the expression evaluates to a value that is not a
real number, that point is not plotted; an error does not occur.
¦
The independent variable in the function is
X
. You may press
,
rather than pressing
ƒ
ã
X
ä
, for the
X
variable. (
Func
MODE
defines the independent variable as
X
.)
¦
The expression is stored as one of the ten user-defined functions in
the
Y=
list as you enter it.
3.
When you complete the expression, press
Í
to move to the
beginning of the next function.