HP 40gs - Manual (Page 282)

16-8 Step-by-Step Examples
Press again to
simplify the result to
Y = 2X+5.
Second method Type:
(-3,-1 )-(-1,3)
The answer is –(2+4i).
With the answer still
selected, apply the
ABS
command by pressing
.
Pressing gives , the same answer as with
method 1 above.
You can also determi1ne the equation of the line by
typing:
DROITE(( -1,3), (-3,-1))
Pressing then gives the result obtained before:
Y = –(2X+5).
Exercise 6
In this exercise, we consider some examples of integer
arithmetic.
Part 1
For n, a strictly positive integer, we define:
1. Compute a
1
, b
1
, c
1
, a
2
, b
2
, c
2
, a
3
, b
3
and c
3
.
2. Determine how many digits the decimal
representations of a
n
and c
n
can have. Show that a
n
and c
n
are divisible by 3.
3. Using a list of prime numbers less than 100, show
that b
3
is a prime.
2 5
AB
a
n
4 10
n
× 1 b
n
2 10
n
1 – × c
n
2 10
n
× 1 + = , = , – =
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