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  1. If   x =
    4ab
    (a ≠ b) , the value of
    x + 2a
    +
    x + 2b
      is;
    a + bx − 2ax − 2b
    1. a
    2. b
    3. 2ab
    4. 2
Correct Option: D

x =
4ab
x
=
2b
a + b2aa + b

By componendo and dividendo,
x + 2a
=
2b + a + b
=
3b + a
x − 2a2b − a − bb − a

Similarly,  
x
=
2a
2ba + b

⇒ 
x + 2a
=
2b + a + b
=
3a + b
x − 2a2b − a − ba − b

∴ 
x + 2a
+
x + 2b
x − 2ax − 2b

=
3b + a
+
3a + b
b − aa − b

=
3b + a − 3a − b
=
2b − 2a
b − ab − a
=
2(b − a)
= 2
b − a



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