Question

3. In the quadratic equation a * x ^ 2 + bx + c = 0 , it is given that b ^ 2 = 4ac . Then the value of x is (A) - b/(2a) (B) (2a)/b (C) - c/(2a) (D) (2c)/a b 2sqrt(ac)​

Answer 1

(2b) 2 −4a(−3c)<04b 2 +12ac<04b 2 <−12ac , b 2 <−3ac , −a>b 2 /(3c) , a<−b 2 /(3c)12ac<0 (4b 2

is a positive number)

either c<0 or a<0

given, 3c/4<(a+b)

3c/4<(−b

2

/3c+b) (putting maximum value of a)

above equation implies,

c<0

Answer 2

(2b) 2 −4a(−3c)<04b 2 +12ac<04b 2 <−12ac , b 2 <−3ac , −a>b 2 /(3c) , a<−b 2 /(3c)12ac<0 (4b 2

is a positive number)

either c<0 or a<0

given, 3c/4<(a+b)

3c/4<(−b

2

/3c+b) (putting maximum value of a)

above equation implies,

c<0

Answer 3

(2b) 2 −4a(−3c)<04b 2 +12ac<04b 2 <−12ac , b 2 <−3ac , −a>b 2 /(3c) , a<−b 2 /(3c)12ac<0 (4b 2

is a positive number)

either c<0 or a<0

given, 3c/4<(a+b)

3c/4<(−b

2

/3c+b) (putting maximum value of a)

above equation implies,

c<0