CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

Given that p and q are the roots of the equation x2 – ax +b =0 and Dn= pn+qn. Find the value of Dn+1 
  1. aDn-bDn-1
  2. aDn
  3. bDn
  4. aDn + bDn-1
  5. Dn


Solution

The correct option is A aDn-bDn-1

Option (a)

Best way to proceed is by assumption of values.

Assume a quadratic equation. Let’s take x2+5x-6=0. Here the roots are p=1 and q=-6

Thus, a = sum of roots = -5 and b= product of roots = -6

D1= p1+q1 = -5

D0 = 2

D2 = 37

Assume n=1

We need to find Dn+1 = D2 = 37

Look in the answer options for 37

Option a is the only one which gives (-5)(-5)-(-6)(2) = 37

flag
 Suggest corrections
thumbs-up
 
0 Upvotes


Similar questions
View More


People also searched for
View More



footer-image