Aptitude - Square Root and Cube Root - Discussion
Discussion Forum : Square Root and Cube Root - General Questions (Q.No. 6)
6.
If a = 0.1039, then the value of 4a2 - 4a + 1 + 3a is:
Answer: Option
Explanation:
4a2 - 4a + 1 + 3a = (1)2 + (2a)2 - 2 x 1 x 2a + 3a
= (1 - 2a)2 + 3a
= (1 - 2a) + 3a
= (1 + a)
= (1 + 0.1039)
= 1.1039
Discussion:
71 comments Page 4 of 8.
Krishna said:
1 decade ago
In a-b formula a<b is the condition so 1-2a is considered a=1 b=2a then 1-2a<0.
1<2a if a=1 then 1<2a.
1<2a if a=1 then 1<2a.
Anoop said:
1 decade ago
Ravi because 2a<1, in our formula we have condition of a>b hope getting me correct me if I'm wrong.
Saniya said:
1 decade ago
The options are correct and even the answer is correct.
By adopting the formula {a+b} = a^2+2ab+b^2.
By adopting the formula {a+b} = a^2+2ab+b^2.
Siddharth said:
10 years ago
Both (1-2a)^2 and (2a-1)^2 are correct we need to see from the options which answer is available.
Renga said:
9 years ago
2a - 1 + 3a = 5a - 1.
= 5(0.1039) - 1 = -0.4805.
Can you please explain, what is (1 - 2a)?
= 5(0.1039) - 1 = -0.4805.
Can you please explain, what is (1 - 2a)?
BhargaV said:
1 decade ago
4a2 - 4a + 1
(2a)2 - 2(2a)(1) + (1)2
(2a - 1)2
so, 2a - 1 + 3a
Why 1 - 2a is here ???
(2a)2 - 2(2a)(1) + (1)2
(2a - 1)2
so, 2a - 1 + 3a
Why 1 - 2a is here ???
DhILDAS said:
1 decade ago
FOMULA (a-b) 2 is ok. But how square has gone from (1-2a) 2 and it written as (1-2a) +3a.
Siri said:
5 years ago
I am not understanding this whole solution, can someone explain to me in an easy manner?
Rathi said:
1 decade ago
@Souji.
(1-2a)2 = (2a-1)2 = 4a2+1-4a.
So no problem.
(1-2a)2 = (2a-1)2 = 4a2+1-4a.
So no problem.
C.M.Rafeek . Moothedam said:
1 decade ago
I got answer 5a-1 ( 5*0.1039 ) - 1 ie -0.4805
How can 2a-1 and 1-2a be equal ?
How can 2a-1 and 1-2a be equal ?
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