4 Group 9
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Question 1.
The derivative of function
f
(
x
)
=
2
-
3
x
3
2
+
3
x
3
is
a)
f
′
(
x
)
=
-
3
x
2
3
(
2
+
3
x
3
)
2
b)
f
′
(
x
)
=
6
x
2
3
(
2
+
3
x
3
)
2
c)
f
′
(
x
)
=
-
4
x
3
(
2
+
3
x
3
)
2
d)
f
′
(
x
)
=
4
x
3
(
2
+
3
x
3
)
2
e)
f
′
(
x
)
=
-
4
x
2
3
(
2
+
3
x
3
)
2
Question 2.
The length
b
of a side of an equilateral triangle is changing at an acceleration
a
. Its perimeter is changing at the acceleration
a)
a
b)
3
b
c)
3
a
b
d)
a
b
e)
3
a
Question 3.
The function
f
(
x
)
=
e
x
(
x
-
1
)
+
2
is increasing on the interval
a)
⟨
-
1
,
1
⟩
b)
⟨
-
1
,
2
⟩
c)
⟨
-
2
,
0
⟩
d)
⟨
-
2
,
2
⟩
e)
⟨
1
,
2
⟩
Evaluate