alleryStart learning →The roots of x^2 + 2x + 5 = 0 are which pair?
A-1 + 4i and -1 - 4i
B1 + 2i and 1 - 2i
C-2 + i and -2 - i
D-1 + 2i and -1 - 2i
Answer & Solution
Correct answer: D. -1 + 2i and -1 - 2i
The discriminant is 4 - 20 = -16, so x = (-2 plus or minus 4i)/2 = -1 plus or minus 2i.
Keep practising Complex Numbers and Quadratic Equations
Browse all Complex Numbers and Quadratic Equations questions for MHT-CET, or explore more Mathematics topics.
Related questions
What is the real part of (2 + i) squared?Evaluate (2 + 3i)(1 - i) and write the result in the form a + bi.Adding two complex numbers on the plane gives the fourth vertex of which shape?Geometrically, multiplying by a complex number does what to the plane?The complex numbers form a real vector space of what dimension?The polynomial x^2 - 2 has no root in which set?The equation x^2 + 4 = 0 has no real root. What are its complex roots?Which number set contains a root of every non-constant polynomial equation?