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Math Challenge II-A 2.29

 
 
KiangZhi Feng Etan的头像
Math Challenge II-A 2.29
KiangZhi Feng Etan - 2020年06月14日 Sunday 21:06
 

Hello! I am completely stumped on problem 2.29 of the Week 2 Assignment. I tried using the Descartes' Rule, but it did not work out, and I am utterly confused. Please help! Thank you!

 
ProfessorAreteem的头像
Re: Math Challenge II-A 2.29
ProfessorAreteem - 2020年06月16日 Tuesday 23:30
 

Start by finding which values of $m$ would give you two real roots by using the discriminant of the equation.

Assume $x_1 < 0$, and $x_2 > 0 $ are the roots of the quadratic equation. What can you say about $x_1x_2$? Then use Vieta's formulas to find an expression for $x_1x_2$ in terms of $m$.