4x方 2y方=1长轴长为多少-搜答案-搜搜考试网

(x²+y²-3)(2x²+2y²-4)=242(x²+y²-3)(x²+y²-2)=24(x²+y²

(x²+y²+1)(x²+y²+3)=8(x²+y²)²+3(x²+y²)+(x²+y²)

因为3x方+xy-2y方=0,即（x+y)(3x-2y)=0,而x+y≠0,所以3x-2y=0原式=[（x+y)^2-4xy]/[(x+3y)(x-y)/(x+3y)(x-3y)=(x-3y)/(x+

[(x²+y²)-(x-y)²+2y(x-y)]/4y=1[x²+y²-(x²-2xy+y²)+2xy-2y²]/4y=

令2/x²=X,则X²-X-3=0（X>0）,解得X=（1+√13）/2令y²=Y,则Y²+Y-3=0（Y≥0）,解得Y=（-1+√13）/2X²+Y

焦点是F(－2,0),则：c=2又：e=c/a=√2/2得：a=2√2则：b²=a²－c²=4得：x²/8＋y²/4=1

先转化到2个未知数用另外一个未知数表示,然后代入求值4x-3y-6z=0x+2y-7z=0解得x=3zy=2z（2x²+3y²+6z²)/(x²+5y²

(2x^4)y³－x³y^4=(x³y³)(2x－y)=(xy)³(2x－y)=4³×(1/16)=4

X+Y=1X³+Y³+3XY=(X+Y)(X²-XY+Y²)+3XY=X²-XY+Y²+3XY=X²+2XY+Y²=(X

直接将二式相乘,得(x²+ax+b)(3x+1)=3x³+x²+3ax²+ax+3bx+b=3x³+(1+3a)x²+(a+3b)x+b由于

8x^2-6y^2=146x^2+4y^2=3814x^2-2y^2=52

2x-4=01+y=0y=-1x=2x方+y方=4+1=5

x方-xy+1/4y方

(X-1/2Y)方

椭圆半焦距：2a^2-2b^2双曲线半焦距：a^2+b^2有相同焦点,2a^2-2b^2=a^2+b^2a^2=3b^2椭圆半焦距：c^2=2a^2-2b^2=4b^2椭圆半焦距c=2b椭圆半长轴=根

x²-y²-x-y=0(x+y)(x-y)-(x+y)=0(x+y)(x-y-1)=0所以x+y=0或者x-y-1=0；4x²-y²+2y-1=04x²

已知x方-4x+4+|y+x|=0,===>(X-2)^2+ly+xl=0====>x=2,y=-2,代入求解即可.（平方数>=0,绝对值>=0)再问：我问一下你的======是什么意思？你能帮我把过

∵x²+y²+6x-2y+10=0∴(x²+6x+9)+(y²-2y+1)=0即(x+3)²+(y-1)²=0由平方的非负性可得(x+3)&

解法一：代数计算,因为点P在圆(x-3)^2+(y-1)^2=4,可设P点坐标为(3+2*cos α,1+2*sin α),α∈[-π, π).于是 |PA|^

基本不等式5分之2根号10

4x方-4xy+y方-4x+2y-15=(2x-y)^2-2(2x-y)-15=(2x-y-5)*(2x-y+3)4x方y方-5x方y方-9y方题目弄错了吧,应该是这样的吧=4x^2y^2-5xy-9