\(\Rightarrow2^{x-1}=32=2^5\\ \Rightarrow x-1=5\\ \Rightarrow x=6\)
2x-1-12=20
2x-1=20+12
2x-1=32
2x-1=25
x-1=5
x=6
2x-1-12=20
b = 1 phần 6 + 1 phần 12 + 1 phần 20 + 1 phần 30 + 1 phần 42 + 1 phần 56 + 1 phần 72
a) 371 + 731 - 271 -531
b) 57 + 58 + 59 + 60 + 61 - 17 - 18 -19 -20 -21
c) 9 - 10 + 11 - 12 + 13 - 14 + 15 - 16
d) - 1 - 2 - 3 - ..... - 2005 - 2006 - 2007
1) x+1/2=-5/3
2) 1/3-x=3/5
4) x-4/3=-7/9
5) x--7/3=5/6
6) x-1/5=9/10
7) x+5/12=3/8
8) x+5/4=7/6
9) x-2/7=1/35
10) x-2/7=-7/10
1) x+1/2=-5/3
2) 1/3-x=3/5
4) x-4/3=-7/9
5) x--7/3=5/6
6) x-1/5=9/10
7) x+5/12=3/8
8) 5/4=7/6
9) x-2/7=1/35
10) x-2/7=-7/10
cả phép tính nữa nha
giúp mình với
9x-2(x-29)=-47
2x-5(x+3)=-75
3x-14=2(x-9)+1
Tìm x
2x-3=x+\(\frac{1}{2}\)
4x-(2x+1)=3-\(\frac{1}{3}\) +x
Tính
a \(\frac{1}{1\cdot4}\) +\(\frac{1}{4\cdot7}\) +\(\frac{1}{7\cdot10}\) +....+\(\frac{1}{100\cdot103}\)
b \(\frac{8}{9}\) -\(\frac{1}{72}\) -\(\frac{1}{56}\) -\(\frac{1}{42}\) -....-\(\frac{1}{6}\) -\(\frac{1}{2}\)
Câu 2: Tính
a/ 30 - 4. (12 + 15)
b/ -16 . 21 + 16 . 63 + 58 . 16
c/ (+12).21 + 21.(-22)
d/ 126 – ( - 4) + 7 – 20
e/ 210 + [46 + (–210) + (–26)]
g/ 100 + (-430) + 2145 + 530
h/ 8. 12 - 8. 5
i/ 25.134 + 25.(-34)
f/ 23 - |19 – 81|.2
