xy不等于0 ,3x^2-2xy-8y^2=0,求x/y的值
问题描述:
xy不等于0 ,3x^2-2xy-8y^2=0,求x/y的值
答
令X/Y=T因为XY不等于0 将3x^2-2xy-8y^2=0同除XY 则得3X/Y-2-8Y/X=0将T代入得3T-2-8/T=0--------(1)因为XY不等于0 则X不等于0 Y不等于0 X/Y也不等于0 即T不等于0将(1)两边同乘T 得 3T^2-2T-8=0 即(T-2)(3T+4...