Algebraeasy · Past Paper
Which of the following equations has imaginary roots?
Ax^2 + 1 = 0
Bx^2 - 1 = 0
Cx^2 + x - 1 = 0
Dx^2 - x - 1 = 0
✓ Correct Answer: A — x^2 + 1 = 0
For x^2 + 1, D = 0^2 - 4(1)(1) = -4. Negative discriminant means imaginary roots.
Share this question
More from Algebra
- If 2x + y = 7 and x + 2y = 8, find the value of x - y.
- Find the value of k for which the system kx - y = 2 and 6x - 2y = 3 has a unique solution.
- If y = 2x and x = 5, find y.
- Solve for x: (x-1)/(x-2) = (x+3)/(x-3)
- A train travels 360 km at a uniform speed. If speed was 5 km/h more, it would take 1 hour less. Find speed.