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1)

The real number k for which the equation,   2x3+3x+k=0   has two  distinct real roots in [0,1]


A) lies between 1 and 2

B) lies between 2 and 3

C) lies between -1 and 0

D) does not exist

Answer:

Option D

Explanation:

Let f(x)= 2x3+3x+k

 On differentiating  w.r,t x , we get

f(x)=6x2+3>0,xϵR

       f(x) is strictly increasing function.

    f(x)= 0 has only one real root, so two roots are not possible