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Byju's Answer
Standard XII
Mathematics
Existence of Limit
If y=2 x 3 ...
Question
If
y
=
2
x
3
−
2
x
2
+
3
x
−
5
, then for
x
=
2
and
Δ
x
=
0.1
value of
Δ
y
is
A
2.002
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B
1.9
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C
0
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D
0.9
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Solution
The correct option is
B
1.9
Given
y
=
2
x
3
−
2
x
2
+
3
x
−
5
⇒
d
y
d
x
=
6
x
2
−
4
x
+
3
⇒
(
d
y
d
x
)
x
=
2
=
24
−
8
+
3
=
19
∵
Δ
y
=
(
d
y
d
x
)
x
=
2
Δ
x
⇒
Δ
y
=
19
×
(
0.1
)
=
1.9
Suggest Corrections
0
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y
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y
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Δ
x
,
Δ
y
and
Δ
z
, respectively, then
z
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y
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y
=
x
y
(
1
±
Δ
x
x
)
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Δ
y
y
)
−
1
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y
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x
/
x
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y
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y
≪
1
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