[中學] 一元二次方程式的根

[chopriabin ()]

假設下列的一元二次方程式有兩根 x_1 and x_2

x^2+k_1\,x+k_2=0,

where k_1 and k_2 are real numbers.

Re (x_1)>0 or Re (x_2)>0 的充分必要條件是？

Re=Real part


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→ pc1234      : k1<0 and k2>0 <---- Routh Hurwitz stability crit
→ pc1234      : erion
→ Tiderus     : 樓上那個是不是兩正根條件？