1．点P是椭圆x^2/25+y^2/16=1上一点,求P到点A(m,0)距离的最小值 设P(x,y)则x²/25+y²/16=1故y²=16(1-x²/25)故|PA|²=(x-m)²+(y-0)²=x²-2mx+m²+16-16x²/25=9x²...