Since your price is _________ __________ ___________ with the prevailing market, it is not ______________ for the buyers on our ______________ to accept.
【简答题】如果x 1 ,x 2 是一元二次方程ax 2 +bx+c=0(a≠0)的两根,那么由求根公式可知, x 1 = -b+ b 2 -4ac 2a , x 2 = -b- b 2 -4ac 2a . 于是有 x 1 + x 2 = -2b 2a =- b a , x 1 - x 2 = b 2 -( b 2 -4ac) 4 a 2 = c a 综上得,设ax 2 +bx+c=0(a≠0)的两根为x 1...