3 Answers

bharat bajaj IIT Delhi
askIITians Faculty 122 Points
8 years ago
Discriminant = b^2 - 4ac
As a>0 , b<0 and c<0
D > 0 , Hence we have two roots. So it could be A or B.
Now, the product of the roots = c/a
Product is negative. Hence, one root is positive and one is negative. Hence, the answer is (B)
Bharat Bajaj
IIT Delhi
askiitians faculty
Sher Mohammad IIT Delhi
askIITians Faculty 174 Points
8 years ago
let roots are a, b
case 1: one root is between (0,1) and another root is greater than 2

ab=8p-15 >=0 imply p>15/8

a+b=2p >2 imply p>1

p belongs (1,inf)

case 2: one root is less than <0 and another root is greater than 2

ab=8p-15<0 imply p<15/8
a+b=2p <2 imply <1
(-inf, 15/8)

hence d is the correct answer

sher mohammad, iit delhi

mycroft holmes
272 Points
8 years ago
Since a>0, the graph is upward facing. Also f(0) <0. Hence (B) is correct

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