Bai 1:
a)Ix-1/2I=1/3
x-1/2=1/3 hay x-1/2=-1/3
x=1/3+1/2hay x=-1/3+1/2
x=2/6+3/6hay x=-2/6+3/6
x=5/6 hay x=1/6
b)Ix-2/3I+1/2=3/4
Ix-2/3I=3/4-1/2
Ix-2/3I=3/4-2/4
Ix-2/3I=1/4
x-2/3=1/4 hay x-2/3=-1/4
x=1/4+2/3hay x=-1/4+2/3
x=3/12+8/12hay x=-3/12+8/12
x=11/12 hay x=5/12
c)1/2Ix-1/2I-1/3=1/4
1/2Ix-1/2I=1/4+1/3
1/2Ix-1/2I=3/12+4/12
1/2Ix-1/2I=7/12
Ix-1/2I=7/12:1/2
Ix-1/2I=7/12x2/1
Ix-1/2I=7/6
x-1/2=7/6 hay x-1/2=-7/6
x=7/6+1/2hay x=-7/6+1/2
x=7/6+3/6hay x=-7/6+3/6
x=5/3 hay x=-2/3
d)1/3I2x-1I+3/2=2
1/3I2x-1I=2-3/2
1/3I2x-1I=4/2-3/2
1/3I2x-1I=1/2
I2x-1I=1/2:1/3
I2x-1I=1/2x3/1
I2x-1I=3/2
2x-1=3/2 hay 2x-1=-3/2
2x=3/2+1hay 2x=-3/2+1
2x=3/2+2/2 hay 2x=-3/2+2/2
2x=5/2 hay 2x=-1/2
x=5/2:2 hay x=-1/2:2
x=5/2x1/2hay x=-1/2x2/1
x=5/4 hay x=-1
Bài 2:
a)-27/23-(-5)/21-4/23+16/21+1/2
=-27/23+5/21-4/23+16/21+1/2
=(-27/23-4/23)+(5/21+16/21)+1/2
=-1+1+1/2
=0+1/2
=1/2
b)8và2/17+13/15+1và15/17+8/19+8/23
=138/17+13/15+32/17+8/19+8/23
=(138/17+32/17)+5681/6555+2760/6555+2280/6555
=10+10721/6555
=
c)-2va2/3+(-0,2)+1,75-5/6+0,2
=-8/3+[(-0,2)+0,2]+7/4+5/6
=-8/3+7/4+5/6
=-32/12+21/12+10/12
=-1/12
d)8/9+1/9x2/9+1/9x7/9
=9/9x3/9x7/9
=189/9
=21/1=21
Bạn ghi lại giúp mình đề câu 2b nhé
