如图y=x² bx c化为y=(x-h) k-搜答案-神马作文网

把4X-4Y=XY化为（4-X)(Y+4)=16怎么化成的?4x-4y-xy=0xy-4x+4y=0y(x+4)-4(x+4)+16=0(x+4)(y-4)=-16(4-x)(4+y)=16

y=2x²+4x-2化为形如y=2(x+1)²-4

y=(2x-4)/7

y=3(x平方+2x/3)=3(x平方+2x/3+1/9-1/9)=3(x平方+2x/3+1/9)-1/3=3(x+1/3)平方-1/3

y=-x²-2x=-(x²+2x+1-1)=-(x²+2x+1)+1=-(x+1)²+1顶点坐标为：(-1,1)

y=2x^2+6x+3=2(x^2+3x)+3=2(x^2+3x+9/4)-9/2+3=2(x+3/2)^2-3/2

后面应该会做了吧

解析y=x²+4x=(x+2)²-4

y=1/2(x-1)平方y=-(x+1)平方

∵(sint+cost)²=sin²t+2sintcost+cos²t=1+2sintcost∴x²=1+2y∴y=x²/2-1/2

x^2＋y^2+z^2=9,y=x.所以:2x^2+z^2=9令根号(2)x=3cosa,则:z=3sina所以参数方程是:x=3根号(2)cosa/2,y=3根号(2)cosa/2,z=3sina(

设A（X1,Y1),-1/X1=-X1+6,即x1^2-6x1-1=0,B(6,0)OA^2-OB^2=X1^2+Y1^2-36=X1^2+(-X1+6)^2-36=2X1^2-12X1=2(x1-6

Y=-X²+4X-4+11=-(X-2)²+11再问：太有才了！O(∩_∩)O谢谢！

极坐标转化时：x=rcosθ,y=rsinθx+y

x²＋y²-4x+10y+4=0(x²-4x+4)+(y²+10y+25)=25(x-2)²+(y+5)²=25

再答：+9后-9

3x-y=0,则y=3x

2x²-5xy-3y²+1=0

两边同乘1+x²得y(1+x²)=1+x+x²去括号得y+yx²=1+x+x²移项yx²-x²-x-1+y=0（y-1)x