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Mathematics
Mathematics
Problem
Which of the following functions is differentiable at
x
=
0
x = 0
x
=
0
? a.
cos
(
∣
x
∣
)
+
∣
x
∣
\cos(|x|) + |x|
cos
(
∣
x
∣
)
+
∣
x
∣
b.
cos
(
∣
x
∣
)
−
∣
x
∣
\cos(|x|) - |x|
cos
(
∣
x
∣
)
−
∣
x
∣
c.
sin
(
∣
x
∣
)
+
∣
x
∣
\sin(|x|) + |x|
sin
(
∣
x
∣
)
+
∣
x
∣
d.
sin
(
∣
x
∣
)
−
∣
x
∣
\sin(|x|) - |x|
sin
(
∣
x
∣
)
−
∣
x
∣
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