If for a quadratic equation b2– 4ac = 205 then roots are…..……
a)equal
b)rational
c)irrational
Solution:If Discriminant is > 0 but not a perfect square then the roots are real, unequal or irrational.
Which of the following is true description of nature of roots of a quadratic equation:
a)real,irrational,equal
b)real,imaginary,unequal
c)real,irrational,unequal
d)Complex,repeated,Rational
If roots of quadratic equation are real,rational or equal, then possible value of discriminant is:
a) 36
b)40
c) 0
d) – 49
Solution:If Discriminant is 0 then the roots are real, equal or rational.
If roots of quadratic equation are imaginary and unequal, then possible value of discriminant is:
a) 0
b)9
c)8
d)-9
Solution:If Discriminant is negative then the roots are imaginary and un equal.
w4 =……….
a)w2
b)w
c)1
d)0
Solution:As w3=1 So,w4=w.w3
=w.1 =w
