GIÚP DÙNG ĐI KHÓ QUÁ !
Tính:
1/(x^2+x)+1/(x^2+3x+2)+1/(x^2+5x+6)+...+1/(x^2+19x+90)= ?
2x ^3 -5x^2+4x-1) : (2x+1)
(x63 -2x+4) ; (x+2)
(6x^3 - 19x^2+23x-12):(2x-3)
(x^4 - 2 x ^3 - 1+ 2 x ):(x^2 - 1)
(6x^3 - 5x^2 + 4x -1 ) : (2x^2-x+1)
(x^4 -5x^2+4):(x^2-3x+2)
a) x(4x+3y)−(y−2x)2
b) (3+x)(x−3)−(x−1)(x2−3)
c)−2(x−3)2+(x+1)(5x−1)
d) (2x+1)(4x2−2x+1)−3x2(x−2)
e) (3x2+19x+20):(3x+4)
f) (7x2+x3+12x−6):(x2+4x−3)
Rút gọn biểu thức;
a) (2x-1)2 - (x+2)2 - 3x2 + 5x
b) (x+2) . ( x-1) + 2 (3x-2)2 + 4x -19x2
c) 2 (3-x) . (x-2) -( 3x+1)2 + 5x - 11x2
Làm phép chia
5x4-3x5+3x-1):(x+1-x2)
(2-4x+3x4+7x2-5x3):(1+x2-x)
17x2+6x4+5x3-23x+7):(7-3x2-2x)
(3x4+11x3-5x2-19x+10):(x2+3x-2)
giúp mình với mai mình thi học kì rồi ..
Câu 1: giải các phương trình sau
a, 3x+2.(x-5)= 6-(5x-1)
b, x^3 - 3x^2-x+3=0
c, 1/x-3 + x/x+3= 2/x^2-9
d, |2x-4|=2+3x
e, 5x-2/3+x= 1+5-3x/2
g, 2/2x-6+ 2/2x+2+2x/(x+1).(3-x)
i, 90/x^2-25= 14/x+5-9/5-x
k, x^4-3x^2+x+13=0
tìm x để 6x^3 - 19x^2 -2 chia hết cho 3x^2 -5x+1
tìm x để 6x^3-19x^2-2 chia hết cho 3x^2 -5x+1
1) (3x-2)/3-2=(4x+1)/42) (x-3)/4+(2x-1)/3=(2-x)/63) 1/2 (x+1)+1/4 (x+3)=3-1/3 (x+2)4) (x+4)/5-x+4=x/3-(x-2)/25) (4-5x)/6=2(-x+1)/2 6) (-(x-3))/2-2=5(x+2)/4 7)2(2x+1)/5-(6+x)/3=(5-4x)/158) (7-3x)/2-(5+x)/5=1 9)(x-1)/2+3(x+1)/8=(11-5x)/310)(3+5x)/5-3=(9x-3)/4