NDA Maths Mock Test – 01 – Q47

The value of x satisfies the inequality [tan^-1x]² – 2 [tan^-1x] – 3 ≤ 0 , where [.] represent greatest integer function, then x lies between

• [-pi/2, tan 1]
• [-tan 1, infinity)
• [-pi/4, tan^-1 3]
• [-tan 1, tan 3]

‘
‘ We ha√e
1 tan” 1x? -2 tan x -3<0 '
‘ Put tan x =a ‘
=a’-20-3<0
1 =a? +a-3a-3<0
‘ Sa@+t1)-3a@+1)<0 '
! = (a+1)(a—3)<0 1
. 5 Ce
-— >=
-! 3
=-1‘ =< tax <3 '
i =-1< tan lx <4
1 = tan(-1) < x ‘ = -tan 1 < xi = X € -tan 1, 00)
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