Question: If a, b, and c are the roots of the equation x3−4x2+3x+5, what is the value of (a+1)(b+1)(c+1)?
Answer:
for cubic equations, ax3+bx2+cx+d, with roots a,b and c
a+b+c=−b/aab+bc+ac=c/aabc=−d/a
(a+1)(b+1)(c+1)=(a+b+c)+(ab+bc+ac)+abc+1=4+3−5+1=3
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