x∧2 (y-5)∧2＝16绕x轴心旋转体-搜答案-智慧作业帮

x*x+4y*y+2x*x-4y+2=0应该是x*x+4y*y+2x-4y+2=0可变换为（x+1)^2+(2y-1)^2=0x=-1,y=1/2,剩下的自己做一下,关键是上面一步要会

（X+2Y)(5X-2Y)

5x平方+8xy-4y平方

[(x+2y)(x-2y)-(2x-y)^2+(3x-y))2x-5y)]/(-x)=(x²-4y²)-(4x²-4xy+y²)+(6x²-17xy+

1)x(x-y)(x+y)-x(x+y)^2=x((x-y)(x+y)-(x+y)^2)=x(x^2-y^2-x^2-2xy-y^2)=x(-2xy-2y^2)=-2xy(x+y)2)（2a+b)(2

因为(x-y)/(x+y)=3,则(x＋y)/(x－y)＝1/3则5(x-y)(x+y)-(x+y)/2(x-y)＝5*3-1/(3*2)=15-1/6=89/6

(x-y)^5*(y-x)^3*(x-y)^2=-(x-y)^5*(x-y)^3*(x-y)^2=-（x-y）^(5+3+2)=-(x-y)^10

x+49=y49=y-x49=(y+x)(y-x)因为x,y是正整数所以y+x>0则y-x=49/(y+x)>0所以y+x>y-x>0而49=7×7=49×1若y+x=7y-x=7解得：x=0y=7x

解析x²+y²+2x-4y+5=0(x+1)²-1+(y-2)²-4+5=0(x+1)²+(y-2)²=0所以x=-1y=2希望对你有帮助学

x=66/37y=-28/37

1)(2x+5y)(2x-5y)(-4x^2-25y^2)=-(4x^2-25y^2)(4x^2+25y^2)=-(16x^4-625y^4)=625y^4-16x^42)[（x+y)(x-y)-(x

原式=-[(x-y)^2-6(x-y)＋9]=-(x-y-3)^2.

绝对值加平方=0因为两者均大于等于0所以都是0|x+y+2|=0(2x+3y+5)²=0x+y=-22x+3y=-5x=-1y=-1有什么不明白可以继续问,随时在线等.

解(x-y)(x+y)-(x-2y)²+x(3x-5y)-(x-y)(x-2y)=(x²-y²)-(x²-4xy+4y²)+(3x²-5xy

原式=-2x(x-2y)把x=-2,y=1/2代入得原式=-12再问：我邻居说是等于-14，你有没有写错啊再答：没错再问：我看看过程再答：(x+2y)²-(x+y)(3x-y)-5y&sup

(x+y)^2-16(x-y)^2

第一种：用平方差公式,原式=(x+y)^2-(4(x-y))^2=(x+y-4(x-y))(x+y+4(x-y))=(5y-3x)(5x-3y)第二种：全展开合并同类项,原式=x^2+y^2+2xy-

3(x-y)²×[-4/15(y-x)³][-3/2(x-y)∧4]=3(x-y)²×[4/15(x-y)³][-3/2(x-y)∧4]=3*4/15*(-3/

你好,原式是一个完全平方式,我们知道a^2-2ab+b^2=(a-b)^2那么题目中a=4(x+y),b=11(x-y)所以原式=[4(x+y)-11(x-y)]^2=[4x+4y-11x+11y]^

你的题目不够清楚,分子和分母请用括号括起来再问：请快点回答?[x-y/2x]+[y/2x][5/x-5]+[x/5-x][5x/x²2xy+y²]-[5y/x²2xy+y

(2X-3y)-(5x-y)

(2X-3y)-(5x-y)=2x-3y-5x+y=2x-5x-3y+y=(2x-5x)+(-3y+y)=-3x-2y这样写总是全过程了吧