• Home
  • If the equation x3 – ax2 + bx – a = 0 has three real roots then the following is true
Question 1:
If the equation x3 – ax2 + bx – a = 0 has three real roots then the following is true
A. a = 1
B. a ≠ 1
C. b = 1
D. b ≠ l
Feedback The given equation x3 – ax2 + bx – a = 0 can be rewritten as:
x (x2 + b) – a(x2 + 1) = 0
In case b = 1, then the equation becomes (x – a)( x2 + 1) = 0
Now here x2 + 1 = 0 will give imaginary roots.
Hence, if the given equation has three real roots, then b ≠ 1.

These questions are from this test. Would you like to take a practice test?

Practice Quadratic Equations Online Test 3 | Englishfreetest.com

  • 20 minutes
  • 10 questions
Do test

Some questions from the same exam

Some other questions you may be interested in