2x的平方-5x-6=0

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2x的平方-5x-6=02x的平方-5x-6=02x的平方-5x-6=02x^2-5x=6=>x^2-(5/2)x=3=>x^2-2x*(5/4)+(5/4)^2=3+(25/16)=>(x-5/4)

2x的平方-5x-6=0
2x的平方-5x-6=0

2x的平方-5x-6=0
2x^2 -5x =6
=>x^2 - (5/2)x=3
=>x^2 - 2x*(5/4) +(5/4)^2 =3 +(25/16)
=>(x- 5/4 )^2 =73/16
=>x - 5/4 = ±√(73/16)
=> x=5/4 ±(√73 )/4 = (5±√73)/4