How do you find the nature of the roots using the discriminant given 4x^2 + x + 5 = 0?

1 Answer
Jan 29, 2018

Nature of roots are complex and x ~~ -0.125+- 1.11i

Explanation:

4x^2+x+5=0

Comparing with standard quadratic equation ax^2+bx+c=0

a=4 ,b=1 ,c=5 Discriminant D= b^2-4ac or

D=1-80 = -79 If discriminant positive, we get two real

solutions, if it is zero we get just one solution, and if it is negative

we get complex solutions. Here discriminant is negative , so it has

complex roots . Quadratic formula: x= (-b+-sqrtD)/(2a) or

x= (-1+-sqrt (-79))/8 or x=-1/8+- sqrt(79i^2)/8 ; [i^2=-1]

or x ~~ -0.125+- 1.11i

Nature of roots are complex and x ~~ -0.125+- 1.11i [Ans]