Aptitude - Surds and Indices - Discussion
Discussion Forum : Surds and Indices - General Questions (Q.No. 2)
2.
| If |  |
a |  |
x - 1 | = | |
b | |
x - 3 | , then the value of x is: |
| b | a |
Answer: Option
Explanation:
| Given |
a | |
x - 1 | = | |
b | |
x - 3 |
| b | a |
 |
|
a | |
x - 1 | = | |
a | |
-(x - 3) | = | |
a | |
(3 - x) |
| b | b | b |
x - 1 = 3 - x
2x = 4
x = 2.
Discussion:
26 comments Page 1 of 3.
URVASHI said:
5 years ago
Simply Cross Multiply them a with a and b with b.
It becomes;
[a ^(x-1) ][a^(x-3)] = [b^(x-1)][b^(x-3)].
Power will get add on both sides.
Then,
a^(2x-4) = b^(2x-4),
Simply, x=2.
It becomes;
[a ^(x-1) ][a^(x-3)] = [b^(x-1)][b^(x-3)].
Power will get add on both sides.
Then,
a^(2x-4) = b^(2x-4),
Simply, x=2.
(4)
Yesubabu said:
4 years ago
@Urvashi.
You are absolutely right, Thanks for explaining.
You are absolutely right, Thanks for explaining.
(3)
SuryaTeja said:
5 years ago
Am not getting this, please explain in detail.
(3)
Frazer Juma said:
5 years ago
Thanks, guys! I understood very well.
(2)
Panther said:
7 years ago
How come 4?
(2)
Ashish said:
7 years ago
I am not geting. How to solve this?
(1)
Shweta said:
7 years ago
@Husain.
When you compare the power then , x-1=-x-3.
Then how you change the sign of ,x-1=x+3?
When you compare the power then , x-1=-x-3.
Then how you change the sign of ,x-1=x+3?
(1)
Sachin d said:
8 years ago
Thanks @Heman.
(1)
Husain SR said:
9 years ago
Here (a/b)^x-1 and (b/a)^x-3 now if we reciprocal b/a to a/b then there is negative sign on it.
(a/b)^-(x-3).
Let compare thier powers;
x - 1 = -(x - 3).
x - 1 = -x + 3
x + x = 1 + 3.
2x = 4
x = 2 is answer.
(a/b)^-(x-3).
Let compare thier powers;
x - 1 = -(x - 3).
x - 1 = -x + 3
x + x = 1 + 3.
2x = 4
x = 2 is answer.
(1)
Lawal Adetunji said:
8 years ago
I am not getting this. Please help me to understand better.
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