Question

Find the value of k if x-1 is the factor of the polynomial k²x³ -4kx²+4k-1 (a) ±1 (b) ± 2 (c) ± 3 (d)o

Answer 1

Step-by-step explanation:

value of k may be +1 or-1.

here since x-1 is factor, so, substitute x=1 and equating the equation to zero.

Answer 2

Answer:

Option (a) is correct.

Step-by-step explanation:

By factor theorem,

if (x - a) is a factor of f(x) then f(a) = 0

Here, since, (x - 1) is a factor of given expression,

f(x)

then f(1) = 0

f(1) =

${k}^{2} {1}^{3} - 4k {( 1)}^{2} + 4k - 1 = 0 \\ => {k}^{2} - 4k + 4k - 1 = 0 \\ => {k}^{2} - 1 = 0 \\ => (k + 1)(k - 1) = 0 \\ => k = 1 \: \: or \: \: k \: = - 1$

Hence, option (a) is correct.