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CHMMC problems
2018 CHMMC (Fall)
6
6
Part of
2018 CHMMC (Fall)
Problems
(1)
2018 Fall Team #6
Source:
4/17/2022
Karina has a polynomial
p
1
(
x
)
=
x
2
+
x
+
k
p_1(x) = x^2 + x + k
p
1
(
x
)
=
x
2
+
x
+
k
, where
k
k
k
is an integer. Noticing that
p
1
p_1
p
1
has integer roots, she forms a new polynomial
p
2
(
x
)
=
x
2
+
a
1
x
+
b
1
p_2(x) = x^2 + a_1x + b_1
p
2
(
x
)
=
x
2
+
a
1
x
+
b
1
, where
a
1
a_1
a
1
and
b
1
b_1
b
1
are the roots of
p
1
p_1
p
1
and
a
1
≥
b
1
a_1 \ge b_1
a
1
≥
b
1
. The polynomial
p
2
p_2
p
2
also has integer roots, so she forms a new polynomial
p
3
(
x
)
=
x
2
+
a
2
x
+
b
2
p_3(x) = x^2 + a_2x + b_2
p
3
(
x
)
=
x
2
+
a
2
x
+
b
2
, where
a
2
a_2
a
2
and
b
2
b_2
b
2
are the roots of
p
2
p_2
p
2
and
a
2
≥
b
2
a_2 \ge b_2
a
2
≥
b
2
. She continues this process until she reaches
p
7
(
x
)
p_7(x)
p
7
(
x
)
and finds that it does not have integer roots. What is the largest possible value of
k
k
k
?
algebra