fx等于4x方加2分之4x方,求faf1-a-搜答案-智慧作业帮

x²-x-1=0,所以x²=x+1,x^4=（x+1）²=x²+2x+1=x+1+2x+1=3x+2,x^5=（3x+2）x=3x²+2x=3（x+1

已知x方加y方减2x加4y等于-5x方+y方-2x+4y+5=0x方-2x+1+y方+4y+4=0(x-1)方+(y+2)方=0所以x-1=0,y+2=0所以x=1,y=-2如果不懂,请追问,祝学习愉

见图

A/（X+2）-B/（A-2）=4X/（X²-4）[A（X-2）]/[（X+2）（X-2）]-[B（X+2）]/[（X+2）（X-2）]=4X/（X²-4）（AX-2A）/（X&#

看你的题目都看了很少时间(x-4)/(x^2-1)÷(x^2-3x-4)/(x^2+2x+1)+1/(x-1)=(x-4)/(x^2-1)[(x^2+2x+1)/(x^2-3x-4)]+1/(x-1)

等于多少啊,是2+11还是2x+11在我回答的右上角点击【采纳答案】再问：2x再答：我就说嘛过程如下：x^2+4x+8=2x+11x^2+2x-3=0(x+3)(x-1)=0x+3=0或x-1=0x=

(x^2+5)/√(x^2+4)=√(x^2+4)+1/√(x^2+4)令t=√(x^2+4),则t≥2y=t+1/t单调递增,t=2时,ymin=5/2再问：那个x方加5怎么就等于根号x方加4加1再

再答：记得采纳哦

x²+2xy+4y²+x²y²+1=8xy(x²-4xy+4y²)+(x²y²-2xy+1)=0(x-2y)²

2-x分之x-x方+4x+4分之4-x方=2-x/x-x²+4x+4/4-x²=2-1-x²+4x+1-x²=2+4x-2x²

定义域：x属于R.值域：[-1,1]

X^2+y^2=4求式=x^2-2√3-y^2=x^2-2√3-4+x^2=2x^2-2√3-4而x^2≤4则X^2=4时,原式最大为-2√3

x^2+y^2=4,设x=2cosa,y=2sina,则x^2-2√3xy-y^2=4(cosa)^2-8√3cosasina-4(sina)^2=4cos2a-4√3sin2a=8cos(2a+60

(x＋y)/(x)=31＋(y/x)=3得：y/x=2则：(x²＋y²)/(x²－xy＋y²)【分子分母同除以x²】=[1＋(y/x)²]/

2x³+3x³-4x³=(2+3-4)x³=x³

x+1/x=4得x^2+2+1/x^2=16x^2+1/x^2=14x四次方加x平方加1分之x平方=x^2/(x^4+x^2+1)=1/(x^2+1+1/x^2)=1/15

x方减2x减3分之3等于2x方加4x减1将等号左边项移到右边,整理得：x平方+6x=0x（x+6）=0x=0或x+6=0x=-6再问：抱歉是我水平不够没表达完整意思是3/（x平方-2x-3）=2x平方

就比喻a+b=5两边平分得a+b+2ab=25那个2就是2ab=2

这个用换元法令a=x/(x²+2)则(x²+2)/x=1/aa+1/a=-10/33a²+10a+3=0(3a+1)(a+3)=0a=-1/3,a=-3x/(x²