Q33 / 54 · JEE Advanced 2018 (Paper 2) · Mathematics

Let E1={x∈ℝ: x≠1 and xx-1>0} and E2={x∈E1: sin-1logexx-1 is a real number}

(Here the inverse trigonometric function sin-1x assumes values in -π2. π2.)
Let f:E1→ℝ be the function defined by fx=loge⁡xx-1
And g:E2→R be the function defined by gx=sin-1⁡loge⁡xx-1 .

LIST-I LIST-II
A. The range of f is P. -∞,11-e∪ee-1, ∞
B. The range of g contains Q. (0, 1)
C. The domain of f contains R. -12,12
D. The domain of g is S. -∞,0∪0, ∞
  T. -∞,ee-1
  U. ( −∞,0 )∪( 1 2 , e e−1 ]
The correct option is:

  • A
    a-p;b-s;c-r;d-q;
  • B
    a-u;b-p;c-t;d-r;
  • C
    a-q;b-r;c-p;d-u;
  • Correct answer
    D
    a-s;b-q;c-p;d-p;

Solution

E1:xx-1>0
Figure
⇒ E1: x∈-∞,0∪1,∞
E2:-1≤ln⁡xx+1≤1
1e≤xx-1≤e
Now xx-1-1e≥0
⇒ e-1x+1ex-1≥0
Figure
⇒ x ϵ -∞,11-e∪1,∞
Also xx-1-e≤0
e-1x-ex-1≥0
Figure
⇒ x∈-∞,11-e∪ee-1, ∞
As Range of xx-1 is R+-1
⇒ Range of f is R-0 or -∞, 0∪0, ∞
Range of g is –π2,π2 -0 or –π2, 0∪0,π2
Now P→4, Q→2, R→1, S→1
Hence A is correct.

Hence, the correct answer is option: 'D'.

More Functions Questions