Aptitude - Surds and Indices - Discussion
Discussion Forum : Surds and Indices - General Questions (Q.No. 15)
15.
| If x = 3 + 22, then the value of |  |
x | - | 1 |  |
is: |
| x |
Answer: Option
Explanation:
|
x | - | 1 | |
2 | = x + | 1 | - 2 |
| x | x |
| = (3 + 22) + | 1 | - 2 |
| (3 + 22) |
| = (3 + 22) + | 1 | x | (3 - 22) | - 2 |
| (3 + 22) | (3 - 22) |
= (3 + 22) + (3 - 22) - 2
= 4.
 |
|
x | - | 1 | |
= 2. |
| x |
Discussion:
48 comments Page 3 of 5.
Harshini said:
9 years ago
In the 4th step, if you see the denominator: (a+b) (a-b) = (a^2-b^2) (using the formula).
It becomes 3^2 -(2 root 2)^2.
Which is 9 - (4 * 2),
=> 9 - 8 = 1.
It becomes 3^2 -(2 root 2)^2.
Which is 9 - (4 * 2),
=> 9 - 8 = 1.
Priyanka said:
9 years ago
Not getting this, can anyone explain clearly?
Raja raviteja said:
9 years ago
^2 = 1.414.
3 + 2^2 = 5.828. Where ^x = ^5.818 = 2.414.
So, ^x - 1/^x = 2.414 - (1/2.414) = 2 =>answer.
3 + 2^2 = 5.828. Where ^x = ^5.818 = 2.414.
So, ^x - 1/^x = 2.414 - (1/2.414) = 2 =>answer.
Rohit said:
9 years ago
Answer is 4 how do you get 2?
Priyanka said:
9 years ago
Why -2 is wriiten at the end ? From where it came ?
Vijay said:
9 years ago
Please explain how they take ^2over it?
Suma said:
9 years ago
Answer is 4 how do you get 2?
Ahmed said:
9 years ago
Actual answer is 4, but why should be 2.
Srinivas said:
10 years ago
4th step is the problem. Where did the denominator go. No proper explanation.
Nicky said:
10 years ago
Why we subtract -2 in 1st step?
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