Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • NCERT
  • If x + 1 is a factor of 2x cube+ axsquare+ 2bx + 1, then find the values of a and b given that 2a – 3b = 4.

If x + 1 is a factor of 2x3+ ax2+ 2bx + 1, then find the values of a and b given that 2a – 3b = 4.

Answers (1)

Solution:

It is given that (x + 1) is a factor of P(x) = 2x3 + ax2 + 2bx + 1 then according to remainder theorem P(–1) is equal to 0.

 P(–1) = 2(–1)3 + a(–1)2 + 2b (–1) + 1
0 = –2 + a – 2b + 1
\Rightarrowa – 2b = 1 … (1)
Given 2a – 3b = 4 … (2)
Solving eq. (1) and (2) by substitution method
2a – 4b = 2                  {multiply eq. (1) by 2}
2a – 3b = 4
–     +     –
–b = –2
b = 2
Put b = 2 in equation (1)
a – 2(2) = 1
a – 4 = 1
a = 1 + 4
a = 5

Posted by

infoexpert27

View full answer

Similar Questions

Latest Question