Question

find the value of a when x^6-ax^5+x^4-ax^3+3x-a+5 (if x=a)​

Answer 1

Answer:

Let p(x) is polynomial of x .

So, p(x) = x^6 - ax^5 + x^4 - ax^3 + 3x -a +2

Given (x-a) is factor of polynomial p(x)

x -a =0

So, x = a

Put x= a in p(x)

P(a) = a^6– a×a^5 + a^4 - a×a^3 + 3a - a +2

= a^6 - a^6 + a^4 - a^4 + 2a + 2

= 2a +2

Here ( x-a) is factor of given polynomial

So, remainder must be 0.

So, p(a) = 0

2a+2 = 0

Hence value of a = -1