1. voi gt nao cua bien x da thuc nhom co gia tri lon nhat
a B= 4x - xmu2 +1
b C= (1-x).(x+2).(x+3).(x+6)
Cho bieu thuc \(A=\left(\frac{x+1}{x-1}-\frac{x-1}{x+1}+\frac{x^2-4x-1}{x^2-1}\right).\frac{x+2016}{x}\)
a, Voi gia tri nguyen nao cua x thi bieu thuc A co gia tri nguyen
b,Voi gia tri nao cua x thi A co gia tri duong
2(2x-3)(3x+2)-2(x+4)(4x-3)+9x(4-x)-6=0 voi gia tri nao cua x thi bt da cho co gt bang 0
\(2\left(2x-3\right)\left(3x+2\right)-2\left(x-4\right)\left(4x-3\right)+9x\left(4-x\right)-6=0\)
<=> \(2\left(6x^2-5x-6\right)-2\left(4x^2+13x-12\right)+25x-9x^2-6=0\)
<=> \(12x^2-10x-12-4x^2-26x+24+25x-9x^2-6=0\)
<=>\(-x^2-11x+6=0\)
<=>\(\left[\begin{array}{nghiempt}x=\frac{-11+\sqrt{145}}{2}\\x=\frac{-11-\sqrt{145}}{2}\end{array}\right.\)
bạn có thể giảng giúp tớ được không ạ ???? cảm ơn nhiều nhak
voi gia tri nao cua a,b thi da thuc x^3+ax^2+2x+b chia het cho x^2+x+1
xet phuong trinh bac an x : x^-(m-)*x+m*(m-3)=0 (1)
a) voi gia tri nao cua m thi phuong trinh (1) co 2 nghiem trai dau
b)voi gia tri nao cua m thi phuong trinh (1) co nghiem x1;x2 thoa man he thuc x mot mu 3 x hai mu 3
CMR cac bieu thuc sau luon co gia tri duong voi moi gia tri cua bien :
a) x1 + x2 + 2
b) ( x + 3 ) . ( x -11 ) + 2003
a)\(x^2+x+2=\left(x^2+2.\frac{1}{2}.x+\frac{1}{4}\right)+\frac{7}{4}=\left(x+\frac{1}{2}\right)^2+\frac{7}{4}\ge\frac{7}{4}>0\)
=>đpcm
b)\(\left(x+3\right)\left(x-11\right)+2003=x^2-8x-33+2003=x^2-8x+1970\)
\(=\left(x^2-2.x.4+16\right)+1954=\left(x-4\right)^2+1954\ge1954>0\)
=>đpcm
chung minh rang bieu thuc sau luon luon co gia tri am voi moi gia tri cua bien: -5-(x-1)(x+2)
cmr bieu thuc sau luon luon co gia tri duong voi moi gia tri cua bien: 3x^2 -5x+3
xet da thuc M=\(\dfrac{13}{4-x}\)
trong cac gia tri nguyen cua x thi gia tri nao lon nhat gia tri nao nho nhat
voi gia tri nao cua bien thi bieu thuc sau co gia tri nho nhat,tim gia tri do
\(\left(x-2013\right)^2+\left(y-2014\right)^2-2015\)
chung minh cac hang dang thuc sau luon co gia tri duong voi moi gia tri cua bien
4)D=x^2 -2x+y^2+4y+6
5)P=(15x - 1)^2+3(7x+3)(x+1) -(x^2 -73)