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Problem
Problem
The sides of
Δ
A
B
C
\Delta ABC
Δ
A
B
C
satisfy the equation
2
a
2
+
4
b
2
+
c
2
=
4
a
b
+
2
a
c
2a^2 + 4b^2 + c^2 = 4ab + 2ac
2
a
2
+
4
b
2
+
c
2
=
4
ab
+
2
a
c
. Then a. the triangle is isosceles b. the triangle is obtuse c.
B
=
cos
−
1
(
7
8
)
B = \cos^{-1}\left(\frac{7}{8}\right)
B
=
cos
−
1
(
8
7
)
d.
A
=
cos
−
1
(
1
4
)
A = \cos^{-1}\left(\frac{1}{4}\right)
A
=
cos
−
1
(
4
1
)
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