Tim x , biet : \(A,[3x - 4] = x ; B, [5x -3] = 2x + 1\)
tim a b biet x ^4-3x +2=(x-1)(x^3+ax^2+bx-2)
tim x biet 50%x+2/3x=x+4
=>1/2x+2/3x=x+4
x(1/2+2/3)=x+4
x7/6=x+4
x7/6-x-4=0
x(7/6-1)-4=0
=>x1/6=4
=>x=24
tim x biet:
a,10-2(4-3x)=-4
b,-12+3(-x+7)=-18
a)10-(8-6x)=-4
10-8+6x=-4
2+6x=-4
6x=-4-2
6x=-6
x=-6:6
x=-1
b)-12+(-3x+21)=-18
-12-3x+21=-18
9-3x=-18
3x=9-(-18)
3x=27
x=27:3
x=9
Tim x biet rang:
a) 4/4^x + 3.4^2-x = 832
b) (3x - 2)^2002 = (3x - 2)^2004
c) /1 - 2x/ + x + 2 = 0
tim x biet /3x+1/+/4-x/=3
nhận xét 3 >0
=> /3x+1/= 3x+1
/4-x/= 4-x
ta có 3x+1 + 4 -x = 3
=> 2x + 5 = 3
=> 2x = -2
=> x= -1
tim x biet
|x+1|+|3x+2|=3x
|x-2|+4|x+1|=x-3
cho x/4=y/5.tim x y biet a) x+y=54 b) 3x -2y=8 c) x.y=80
tim x biet : 2^3x+2 = 4^x+5
Tim x biet:
a,[3x-4]=x
b,[x+8]=-3.x
c,[5x-3] = 2x+1