Getting started
TI-85/86 calculators, 5
Repeat this process for the other two values in the table below. Only the values
at
−
27 and
x
= 8 are exact because only
−
27 and 8 of the
x
-values are perfect cubes.
x
y
= 5
x
1
/
3
.
=
x
y
= 5
x
1
/
3
.
=
−
27
−
15
−
30
−
15
.
5361625298
4
7
.
93700525984
10
10
.
7721734502
6
9
.
08560296416
8
10
Exercises
Use your calculator or computer to find the approximate decimal values of the expressions in Exercises T1
through T8. Do not simplify the expressions before entering them and be sure your machine is in radian
mode for the trigonometric function in Exercise T1. In some cases extra parentheses are needed to express
numerators, denominators, and exponents.
1.
O
(a)
√
6 cos(9
/
7)
(b)
6 cos(
π/
7
3
) (Edit the expression from part (a).)
2.
O
(
−
5
−
1
.
63
×
10
−
2
)
−
1
3.
O
2 + 8
4
−
6
−
3
5
−
1
4.
O
A
+
BC
D
with
A
= 7,
B
= 6,
C
= 5
,
and
D
= 4 (Store the values first.)
5.
O
1
2
log
10
(7)
6.
O
1
.
34
×
10
6
−
4
×
10
5
7
.
12
×
10
−
8
7.
O
√
4 + 7
8
−
10
8.
O
(
−
32)
4
/
5
Outlines of solutions
1a.
0
.
688885143177
•
(If your result is 2
.
44887304686, your calculator is not in radian mode.)
•
Press
2nd
√
6
cos
(
9
÷
7
)
to have the screen read
√
6 cos (9
/
7). Then press
ENTER
for the answer.
1b.
5
.
999748331
•
If your last operation was the calculation of
√
6 cos (9
/
7), press
2nd
ENTRY
to put it back on the screen. If you performed other calculations, type
√
6 cos (9
/
7) again. Press
J
until the cursor is over the square root sign and press
DEL
to delete it. Move the cursor
to the 9 and press
2nd
π
to replace the 9 with
π
. Put the cursor on the close parenthesis and
press
2nd
INS
. Press
∧
3
to insert
∧
3 before the close parenthesis, so the screen reads
6 cos(
π/
7
∧
3), and press
ENTER
for the answer.
2.
−
0
.
199350118613
•
Press
(
(
−
)
5
−
1
.
6
3
EE
(
−
)
2
)
2nd
x
−
1
to display
(
–
5
−
1
.
63
e
–
2)
−
1
. (
A
e
n
stands for
A
×
10
n
.) Press
ENTER
for the answer. Notice that
(
−
)
is
for negation,
−
is for subtraction, and
x
−
1
is for taking reciprocals.
3.
−
86
•
Use
(
2
+
8
)
÷
(
4
−
6
)
−
3
∧
(
5
−
1
)
to display
(2 + 8)
/
(4
−
6)
−
3
∧
(5
−
1). Press
ENTER
for the answer.
