Question

find the range of k for which the roots are imaginary for (k-3)x²+4(k-3)x+4=0

Answer 1

for imaginary roots det should be less than zero
b^2-4ac<o
16(k-3)^2-16(k-3)< 0
(k-3)(k-4)< 0
range of k is (3,4)