Official Quant thread for CAT 2013

@albiesriram said:
Here 8th is unsolved . OA for 7 is B solved by@Subhashdec2New set
is it option B for 8??

(-4,4)

albiesriram

8. option d
@Subhashdec2 said:

only 1 value?
@Subhashdec2 said:
is it option B for 8??(-4,4)
No for both
@Tusharrr said:
If a,b and c are non-zero reals such that a+b+c=11and 1/a+1/b+1/c=0, what is the value of a^2+b^2+c^2?
121.

albiesriram

9 . option d
10. option a
@psk.becks said:
albiesriram9 . option d10. option a
@albiesriram said:
Here 8th is unsolved . OA for 7 is B solved by@Subhashdec2New set
Q1 a1 + a3 + a5 = -12
=> a3 = -4

a1 = (-4 - 2d), a2 = (-4 - d)

a1*a2*a3 = 8
a1*a2 = -2
(4 + 2d)(4 + d) = -2
2d^2 + 12d + 18 = 0
d^2 + 6d + 9 = 0
d = -3

a2 = -1, a4 = -7, a6 = -13

a2 + a4 + a6 = -21

Q2 if x > 3, then
(x - 3) + ˆš(x^2 - 6x + 6) = 1
x^2 - 6x + 6 = x^2 - 8x + 16
x = 5 (doesn;t satisfy)

if x is less than or equal to 3, then
(3 - x) + ˆš(x^2 - 6x + 6) = 1
x^2 - 6x + 6 = x^2 - 4x + 4
x = 1 (doesn't satisfy)

No solution
how many integers satisfy the inequality
∣ 10(x+1)/(x^2+2x+3) ∣≥1?


Details : a this line sign is of absolute of a
@albiesriram said:
dusre wale ka (-4,4) hai . confirm karo?
@zuloo said:
dusre wale ka (-4,4) hai . confirm karo?
No :(

Tusharrr

18 integers????
@psk.becks said:
Tusharrr18 integers????
Approach?

OA for 9,10 is D n A


11 &12


@albiesriram said:
No
it could be [0,4) but with open bracket for 4. i am not too sure.

albiesriram

for quad. x^2+2x+3 -->no real roots hence always +ve(mod fn. useless)
check the solutions for X^2+2X+3 = 10(x+1) X >= -1
X^2+2X+3 = -10(x+1) X
@psk.becks good i m getting it 10 but the answer is 18 how
@albiesriram said:
Here 8th is unsolved . OA for 7 is B solved by@Subhashdec2New set
9 D) 10 A) imo
@albiesriram said:
OA for 9,10 is D n A11 &12
11. b?
substitute x=1, 2, 0...we get unique values for a and b

12. d?
x2 =0
x2 -x = 0
x2 -2x + 1 = 0
x2 +x + 1 = 0

albiesriram

11. option b
12. option c
@RDN said:

12. d?
12 ko c aa raha hein