设f(x,y)=0,g (x y)=0 是两曲线的方程,求证方程f(x y)+λg(x y)=0表示经过这两条曲线的交点的曲线。这是十年制学校高中第二册复习题六的第一题的第(4)小题它的正确性,我们已经证明,还可证明其逆命题也成立。我们把方程f(x,y)+λg(x,y)=0(λ为任何实数)叫做经过两曲线f(x,y)=0和g(x,y)=0的交点的曲线系方程。(不包括曲线g(x,y)=0) 直线系方程和圆系方程是曲线系方程的两个 Let f(x,y)=0 and g(x y)=0 be the equations of the two curves. The verification equation f(x y)+λg(x y)=0 represents the curve passing through the intersection of these two curves. This is the correctness of the fourth question of the first question of the second-year review of the 10th-year high school school (6). We have already proved that it can also prove that the contradictory issue is also valid. We call the equation f(x,y)+[lambda]g(x,y)=0([lambda] for any real number) as a curve passing through the intersection of two curves f(x,y)=0 and g(x,y)=0. equation. (Excluding the curve g(x,y)=0) Linear equations and circular equations are two of the curve equations