A quadratic equation is given as $x^2+2(a-1)x+(a-5)=0$ then what could be the possible value of a if:
a) The equation has positive roots
b) The equation has roots of opposite sign
c) The equation has negative roots
I tried to check the nature of discriminant but it takes me nowhere.Can someone tell me the best procedure to deal with such sums?Or hints atleast..