HELP~~数学题~~
解:
y=x+1
A(x1,y1)、B(x2,y2)
x1+x2=-2/3, y1+y2=x1+x2+2=4/3
mx1²+ny1²=1
mx2²+ny2²=1
相减,得m(x1²-x2²)+n(y1²-y2²)=0
m(x1+x2)(x1-x2)+n(y1+y2)(y1-y2)=0
-2m(x1-x2)/3+4n(y1-y2)/3=0
(y1-y2)/(x1-x2)=m/2n=1 (直线的斜率)
m=2n
双曲线y²/4n²-x²/n²=1
渐近线为y=±2x
锐角为2...全部
解:
y=x+1
A(x1,y1)、B(x2,y2)
x1+x2=-2/3, y1+y2=x1+x2+2=4/3
mx1²+ny1²=1
mx2²+ny2²=1
相减,得m(x1²-x2²)+n(y1²-y2²)=0
m(x1+x2)(x1-x2)+n(y1+y2)(y1-y2)=0
-2m(x1-x2)/3+4n(y1-y2)/3=0
(y1-y2)/(x1-x2)=m/2n=1 (直线的斜率)
m=2n
双曲线y²/4n²-x²/n²=1
渐近线为y=±2x
锐角为2arctan(1/2)。
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