Fermi
·
Concept Library
·
Courses
·
Books
·
Problems
·
Simulations
·
Math Wiki
·
High School
Fermi
›
Problems
Mathematics
Mathematics
Problem
For any arithmetic progression
(
a
n
)
(a_n)
(
a
n
)
, which of the following equations is ALWAYS true? a)
a
3
+
a
7
=
2
a
6
a_3 + a_7 = 2a_6
a
3
+
a
7
=
2
a
6
b)
a
1
+
a
4
=
2
a
3
a_1 + a_4 = 2a_3
a
1
+
a
4
=
2
a
3
c)
a
1
+
a
5
=
2
a
3
a_1 + a_5 = 2a_3
a
1
+
a
5
=
2
a
3
d)
a
2
+
a
6
=
2
a
5
a_2 + a_6 = 2a_5
a
2
+
a
6
=
2
a
5
Browse the problem library