Problem2x2−3x−2=02x^2 - 3x - 2 = 02x2−3x−2=0Step-by-step solution辨識 a=2a = 2a=2、b=−3b = -3b=−3、c=−2c = -2c=−2。計算判別式:Δ=(−3)2−4(2)(−2)=9+16=25\Delta = (-3)^2 - 4(2)(-2) = 9 + 16 = 25Δ=(−3)2−4(2)(−2)=9+16=25。套用二次公式:x=3±252⋅2=3±54x = \frac{3 \pm \sqrt{25}}{2 \cdot 2} = \frac{3 \pm 5}{4}x=2⋅23±25=43±5。兩個解:x1=3+54=2x_1 = \frac{3 + 5}{4} = 2x1=43+5=2 與 x2=3−54=−12x_2 = \frac{3 - 5}{4} = -\frac{1}{2}x2=43−5=−21。Answerx=2orx=−12x = 2 \quad \text{or} \quad x = -\tfrac{1}{2}x=2orx=−21Want to solve a different problem? Open the quadratic solver →Related worked examples/solve/algebra/x2-plus-5x-plus-6/solve/algebra/x2-minus-9Read more/blog/mastering-quadratic-equations-complete-guide