# The range of a for which the equation x^2+ax-4=0 has its smaller root in the interval (-1,2) is

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The range of a for which the equation x^2+ax-4=0 has its smaller root in the interval (-1,2) is
A. (-infty, -3)
B. (0, 3)
C. (0, infty)
D.  (- infty, - 3 ) cup (0, infty)

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Clearly , f(-1) gt 0 , f(2) lt 0
Now ,
 f(0) = - 4 lt 0
rArr f (-1) = 1 - a - 4 gt 0
and  f(2) = 4 + 2 a - 4 lt 0
rArr a lt - 3 and alt 0
rArr a in (-infty), - 3)