If `n-1C_r=(k^2-3)^nC_(r+1),` then (a) `(-oo,-2]` (b) `[2,oo)` (c) `[-sqrt3, sqrt3]` (d) `(sqrt3,2]`

If (n-1)C_(r)=(k^(2)-3)nC_(r+1), then k belong to

Which of the following is irrational? (a) (2-sqrt3)2 (b) (sqrt2+sqrt3)2 (c) (sqrt2-sqrt3)(sqrt2+sqrt3) (d) (2sqrt7)/7

Delta ABC has a right angle at A. If BC = sqrt2 and AB = AC = 1 then sin B is equal to (a) (1)/(sqrt2) (b) sqrt2 (c) (sqrt3)/(2) (d) sqrt3

The set of value of a for which both the roots of the equation x^2-(2a-1)x+a=0 are positie is (A) {(2-sqrt(3))/2} (B) {(2-sqrt(3))/2,(2+sqrt(3))/2} (C) [(2+sqrt(3)/2,oo) (D) none of these

The set of all real numbers x for which x^2-|x+2|+x >0 is (a)(-oo,-2)uu(2,oo) (b) (-oo,-sqrt(2))uu(sqrt(2),oo) (c)(-oo,-1)uu(1,oo) (d) (sqrt(2),oo)

If a=(sqrt(3))/(2), then sqrt(1+a)+sqrt(1-a)=?(2-sqrt(3))(b)(2+sqrt(3))(c)((sqrt(3))/(2))(d)sqrt(3)

The value of tan 45^@ (A) sqrt3 (b) frac(sqrt3)(2) (C) frac(1)(sqrt3) (D) 1

Tangents drawn from (2, 0) to the circle x^2 + y^2 = 1 touch the circle at A and B . Then (A) A-= (1/2, sqrt(3)/2) , B -= (-1/2, - sqrt(3)/2) (B) A-= (- 1/2, (-sqrt(3)/2) , B -= (1/2, sqrt(3)/2) (C) A-= (1/2, sqrt(3)/2) , B-= (1/2, - sqrt(3)/2) (D) A-= (1/2, - sqrt(3)/2), B-= (1/2, sqrt(3)/2)