1
You visited us
1
times! Enjoying our articles?
Unlock Full Access!
Byju's Answer
Standard VIII
Mathematics
Identity (a^3+b^3)
2 x+5 x4 x 2-...
Question
(
2
x
+
5
x
)
(
4
x
2
-
10
+
25
x
2
)
=
A
8
x
3
+
125
x
3
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
4
x
3
+
125
x
2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
4
x
2
+
25
x
3
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
8
x
2
+
25
x
2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is
A
8
x
3
+
125
x
3
The given expression is
(
2
x
+
5
x
)
(
4
x
2
−
10
+
25
x
2
)
T
a
k
i
n
g
a
=
2
x
a
n
d
b
=
5
x
, we get
(
a
+
b
)
(
a
2
−
a
b
+
b
2
)
Using identity we have
(
a
+
b
)
(
a
2
−
a
b
+
b
2
)
=
a
3
+
b
3
Hence,
(
2
x
+
5
x
)
(
4
x
2
−
10
+
25
x
2
)
=
(
2
x
)
3
+
(
5
x
)
3
=
8
x
3
+
125
x
3