Most Important Selected Qs for JEE AdvancedMathematicsInverse Trigonometric Functions
Paragraph: Let f(x)= 4 + ⁻¹ ( x 1+x^2 )- ⁻¹ x and a_i (a_i Question: The value of _ i=1 ^n a_i is equal to:
Options
- A1
- B2
- C3
- D4
Correct answer
C. 3
Step-by-step solution
aligned & f(x)= 4 + ⁻¹ ( x 1+x^2 )- ⁻¹ x & f(x)= 4 + ⁻¹ x- ⁻¹ x & = 3 4 -2 ⁻¹ x x>0 & sgn (f(x))=1 f(x)>0 & 3 4 -2 ⁻¹ x>0 ⁻¹ x aligned & P(x)=x^2-4 k x+3 k^2 & P(x) < 0 x (a₁, a₂ ) & P(1) 0 and P(2) 0 & 1-4 k+3 k^2 0 and 4-8 k+3 k^2 0 aligned (3 k-1)(k-1) 0 (3 k-2)(k-2) 0 k [ 1 3 , 1 ] ... (1) k [ 2 3 , 2 ] ... (2) Intersection of eqns. (1) and (2) is k [ 2 3 , 2 ]