SSC CGL 9 Aug 2017 Shift 1 Paper

© examsiri.com

Question : 63 of 100

Marks: +1, -0

If

x - y - √18 = - 1

and

x + y -3 √ 2 = 1

, then what is the value of

12xy (x ^2 - y ^2 )

?

0
1
$512√2$
$612√2$

Solution:

x - y - √18 = - 1

⇒

x - y = √18-1

...(i)

x + y -3 √ 2 = 1

⇒

x + y = 3√2+1

...(ii)
On solving Eqs. (i) and (ii),

x = 3√2, y =1

∴

12xy (x ^2 - y ^2) = 12 × 3√2 × [(3√2)^2

- (1) ^2] = 612√2

© examsiri.com

Go to Question:

Prev Question

Next Question