Question

please answer to my question please it's urgent with explaination​

Answer 1

x-1=0

x=1

putting the value of x in the eqn we have

f(1)k^2-4k-1=0

k=4+_

$\sqrt{16 + 4} \div 2$

=4+_

$2 \sqrt{5} \div 2$

k=2+_

$\sqrt{5}$