I dont know how to start....any help is appreciated!!

z51

New member
Joined
Mar 11, 2021
Messages
8
Assume that ߙ a and b are positive real numbers with a not equal to b ,such that: 2a^2 +2b^2= 5ab The value of the expression |(a+b)/(a-b)| is equal to:
Α. 1
Β. 2
c. 3
d. 4
Ε. 5
 
Assume that ߙ a and b are positive real numbers with a not equal to b ,such that: 2a^2 +2b^2= 5ab The value of the expression |(a+b)/(a-b)| is equal to:
Α. 1
Β. 2
c. 3
d. 4
Ε. 5
To start you off:

Since a > b and a>0 and b>0 then (a-b)>0............................... continue

Please show us what you have tried and exactly where you are stuck.

Please follow the rules of posting in this forum, as enunciated at:


Please share your work/thoughts about this problem.
 
An alternative way to start is

[MATH]2a^2 + 2b^2 = 5ab \implies a = \dfrac{-(-5b)\pm \sqrt{(-5b)^2 - 4(2)(2b^2)}}{2 * 2} = \dfrac{5b \pm 3b}{4} \implies[/MATH]
[MATH]a = 0.5b \text { or } a = 2b.[/MATH]
This may relate more obviously to mathematical facts that you already are familiar with.

The main point is: when you are unsure of where to start, try things.
 
Last edited:
Top