Let a,b,c,d be four integers such that ad is odd and bc is even,then ax3+bx2+cx+d = 0 has
(a) at least one irrational roots
(b) all three rational roots
(c) all three integral roots
(d) none of these
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2 Answers
1708\hspace{-16}$Let $\bf{a=1\;,d=1}$ and $\bf{b=2\;,c=2}$. Then\\\\ Equation is $\bf{x^3+2x^2+2x+1=0}$\\\\ $\bf{(x+1).(x^2+x+1)=0}$\\\\ So $\bf{x=-1\in \mathbb{Z}}$\\\\ and $\bf{x=\frac{-1\pm i.\sqrt{3}}{2}\in\mathbb{C}}$\\\\
21So what can be concluded from this...no real roots??And anything else?