<img src="https://latex.codecogs.com/svg.image?\bg_white&space;\\(y-y_1)=k(x-x_1)^2&space;\\(y_2-y_1)=k(x_2-x_1)^2\\k=\frac{(y_2-y_1)}{(x_2-x_1)^2}\\(x_2-x_1)^2(y-y_1)=(y_2-y_1)(x-x_1)^2\\(x_2-x_1)^2y=(y_2-y_1)(x^2-2x_1x+{x_1}^2)+(x_2-x_1)^2y_1\\(x_2-x_1)^2y=(y_2-y_1)x^2+2x_1(y_1-y_2)x+(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1\\&space;a=(x_2-x_1)^2\\b=&space;(y_2-y_1)\\c=&space;2x_1(y_1-y_2)\\d=&space;(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1" title="\bg_white \\(y-y_1)=k(x-x_1)^2 \\(y_2-y_1)=k(x_2-x_1)^2\\k=\frac{(y_2-y_1)}{(x_2-x_1)^2}\\(x_2-x_1)^2(y-y_1)=(y_2-y_1)(x-x_1)^2\\(x_2-x_1)^2y=(y_2-y_1)(x^2-2x_1x+{x_1}^2)+(x_2-x_1)^2y_1\\(x_2-x_1)^2y=(y_2-y_1)x^2+2x_1(y_1-y_2)x+(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1\\ a=(x_2-x_1)^2\\b= (y_2-y_1)\\c= 2x_1(y_1-y_2)\\d= (y_2-y_1){x_1}^2+(x_2-x_1)^2y_1" />
https://latex.codecogs.com/svg.image?\bg_white&space;\\(y-y_1)=k(x-x_1)^2&space;\\(y_2-y_1)=k(x_2-x_1)^2\\k=\frac{(y_2-y_1)}{(x_2-x_1)^2}\\(x_2-x_1)^2(y-y_1)=(y_2-y_1)(x-x_1)^2\\(x_2-x_1)^2y=(y_2-y_1)(x^2-2x_1x+{x_1}^2)+(x_2-x_1)^2y_1\\(x_2-x_1)^2y=(y_2-y_1)x^2+2x_1(y_1-y_2)x+(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1\\&space;a=(x_2-x_1)^2\\b=&space;(y_2-y_1)\\c=&space;2x_1(y_1-y_2)\\d=&space;(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1" title="\bg_white \\(y-y_1)=k(x-x_1)^2 \\(y_2-y_1)=k(x_2-x_1)^2\\k=\frac{(y_2-y_1)}{(x_2-x_1)^2}\\(x_2-x_1)^2(y-y_1)=(y_2-y_1)(x-x_1)^2\\(x_2-x_1)^2y=(y_2-y_1)(x^2-2x_1x+{x_1}^2)+(x_2-x_1)^2y_1\\(x_2-x_1)^2y=(y_2-y_1)x^2+2x_1(y_1-y_2)x+(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1\\ a=(x_2-x_1)^2\\b= (y_2-y_1)\\c= 2x_1(y_1-y_2)\\d= (y_2-y_1){x_1}^2+(x_2-x_1)^2y_1
https://latex.codecogs.com/svg.image?\bg_white&space;\\(y-y_1)=k(x-x_1)^2&space;\\(y_2-y_1)=k(x_2-x_1)^2\\k=\frac{(y_2-y_1)}{(x_2-x_1)^2}\\(x_2-x_1)^2(y-y_1)=(y_2-y_1)(x-x_1)^2\\(x_2-x_1)^2y=(y_2-y_1)(x^2-2x_1x+{x_1}^2)+(x_2-x_1)^2y_1\\(x_2-x_1)^2y=(y_2-y_1)x^2+2x_1(y_1-y_2)x+(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1\\&space;a=(x_2-x_1)^2\\b=&space;(y_2-y_1)\\c=&space;2x_1(y_1-y_2)\\d=&space;(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1" title="\bg_white \\(y-y_1)=k(x-x_1)^2 \\(y_2-y_1)=k(x_2-x_1)^2\\k=\frac{(y_2-y_1)}{(x_2-x_1)^2}\\(x_2-x_1)^2(y-y_1)=(y_2-y_1)(x-x_1)^2\\(x_2-x_1)^2y=(y_2-y_1)(x^2-2x_1x+{x_1}^2)+(x_2-x_1)^2y_1\\(x_2-x_1)^2y=(y_2-y_1)x^2+2x_1(y_1-y_2)x+(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1\\ a=(x_2-x_1)^2\\b= (y_2-y_1)\\c= 2x_1(y_1-y_2)\\d= (y_2-y_1){x_1}^2+(x_2-x_1)^2y_1
不知道要怎麼插入圖片...
[tex]\bg_white \\(y-y_1)=k(x-x_1)^2 \\(y_2-y_1)=k(x_2-x_1)^2\\k=\frac{(y_2-y_1)}{(x_2-x_1)^2}\\(x_2-x_1)^2(y-y_1)=(y_2-y_1)(x-x_1)^2\\(x_2-x_1)^2y=(y_2-y_1)(x^2-2x_1x+{x_1}^2)+(x_2-x_1)^2y_1\\(x_2-x_1)^2y=(y_2-y_1)x^2+2x_1(y_1-y_2)x+(y_2-y_1){x_1}^2+(x_2-x_1)^2y_1\\ a=(x_2-x_1)^2\\b= (y_2-y_1)\\c= 2x_1(y_1-y_2)\\d= (y_2-y_1){x_1}^2+(x_2-x_1)^2y_1[/tex]