official quant thread for cat08

[parthatayi]

Originally Posted by dheeraj.del

Suppose 2 more people were invited - x& y -
The combinations for dance are -
Amrita & x
Amrita & y
Satyam & x
Satyam & y
x & y
i.e. total of 5 combinations. this is satisfied 3n -7 i.e. 3*4 - 7 = 5. hence the answer

how abt when n=7...the answer should be 20...but the expression 3n-7 does not yield 20 for n=7

[masoom]

hey guys.. i got confused big tym on this problem..

area of the bounded region by :

|x+y|+|x-y|=4...

[Fuzon]

hey guys.. i got confused big tym on this problem..

area of the bounded region by :

|x+y|+|x-y|=4...

Answr : Is the answer 8 units??

Reasoning:

LHS and RHS wd be same in case of foll values

(2,2),(-2,-2),(2,-2),(-2,2)

So the fig formed is a square with diagonal of 4 and side of 2Root2

Thus area bound is (2root2)^2 = 8 units ....

answrs plz

[parthatayi]

Originally Posted by Fuzon

Answr : Is the answer 8 units??

Reasoning:

LHS and RHS wd be same in case of foll values

(2,2),(-2,-2),(2,-2),(-2,2)

So the fig formed is a square with diagonal of 4 and side of 2Root2

Thus area bound is (2root2)^2 = 8 units ....

answrs plz

yeah answer is 8 sq units

[dare2]

Originally Posted by masoom

hey guys.. i got confused big tym on this problem..

area of the bounded region by :

|x+y|+|x-y|=4...

is it 8 square units?

[v-factor]

Originally Posted by masoom

hey guys.. i got confused big tym on this problem..

area of the bounded region by :

|x+y|+|x-y|=4...

The area should be bounded between lines x=+2, x=-2, y=+2 and y=-2
16 square units.

[masoom]

Originally Posted by Fuzon

Answr : Is the answer 8 units??

Reasoning:

LHS and RHS wd be same in case of foll values

(2,2),(-2,-2),(2,-2),(-2,2)

So the fig formed is a square with diagonal of 4 and side of 2Root2

Thus area bound is (2root2)^2 = 8 units ....

answrs plz

answer is ryt..

yups these 4 points will satisfy the equation..

but how do u proceed further to decide that the square will be of diagonal 4...

[atul011]

Originally Posted by masoom

hey guys.. i got confused big tym on this problem..

area of the bounded region by :

|x+y|+|x-y|=4...

I am getting the side as 4 unit and the area as 16 units.

[dare2]

Originally Posted by masoom

answer is ryt..

yups these 4 points will satisfy the equation..

but how do u proceed further to decide that the square will be of diagonal 4...

joining the four points gives 4 triangles with base and height 2.

[masoom]

Originally Posted by dare2

joining the four points gives 4 triangles with base and height 2.

yups in that way i got it..

but i had a silliest of doubt...

do all the points on the line joining these points satisfy the given equation...