3.Find the value of k, if x – 1 is a factor of p(x) in each of the following cases :

i)\(p(x) = x^2 + x + k\)

ii)\(p(x) = 2x^2 + kx + \sqrt{2}\)

iii)\(p(x) = kx^2 - \sqrt{2}x + 1\)

iv)\(p(x) = kx^2 - 3x + k\)

i)\(p(x) = x^2 + x + k\)

ii)\(p(x) = 2x^2 + kx + \sqrt{2}\)

iii)\(p(x) = kx^2 - \sqrt{2}x + 1\)

iv)\(p(x) = kx^2 - 3x + k\)

The zero of x - 1 is 1.

i)So, as x - 1 is a factor of \(p(x) = x^2 + x + k\), therefore, \(p(1) = 0\)

i.e. \(0 = (1)^2 + 1 + k\)

i.e.\(0 = 1 + 1 + k\)

i.e.\(0 = 2 + k\)

i.e.\(k = -2\)

ii)So, as x - 1 is a factor of \(p(x) = 2x^2 + kx + \sqrt{2}\), therefore, \(p(1) = 0\)

i.e. \(0 = 2(1)^2 + k(1) + \sqrt{2}\)

i.e.\(0 = 2 + k + \sqrt{2}\)

i.e.\(k = -2 - \sqrt{2}\)

iii)So, as x - 1 is a factor of \(p(x) = kx^2 - \sqrt{2}x + 1\), therefore, \(p(1) = 0\)

i.e. \(0 = k(1)^2 - ( \sqrt{2})1 + 1\)

i.e.\(0 = k - \sqrt{2} + 1\)

i.e.\(k = \sqrt{2} - 1\)

iv)So, as x - 1 is a factor of \(p(x) = kx^2 - 3x + k\), therefore, \(p(1) = 0\)

i.e. \(0 = k(1)^2 - 3(1) + k\)

i.e.\(0 = k - 3 + k\)

i.e.\(3 = 2k\)

i.e.\(k = 3/2\)