Sponsor Area

Complex Numbers And Quadratic Equations

Question
CBSEENMA11015656

If the equation anxn +an-1xn-1 +....... +a1x =0, a1 ≠ 0, n≥2, has a positive root x =  α, then the equation nanxn-1 + (n-1)an-1xn-2 +......+a1 = 0 has a positive root, which is

  • greater than α

  • smaller than α

  • greater than or equal to α

  • equal to α

Solution

B.

smaller than α

f(0) = 0, f(α) = 0
⇒ f′(k) = 0 for some k∈(0, α).