Giải

$\begin{array}{c}15,{25}^o=15\frac{1^o}{4}={15}^o{15}^{\prime }={915}^{\prime }\\ 30,5^o=30\frac{1^o}{2}={30}^o{30}^{\prime }={1830}^{\prime }\\ 60,{75}^o=60\frac{3^o}{4}={60}^o{45}^{\prime }={3645}^{\prime }\\ 90,2^o=90\frac{1^o}{5}={90}^o{12}^{\prime }={5412}^{\prime }\\ 45,{15}^o=45\frac{3^o}{20}={45}^o{9}^{\prime }={2709}^{\prime }\end{array}$

Để đây mik viết rõ ra nhé !!!

30,5o = 30(1/2)o = 30o30’ = 1830’

60,75o = 60(3/4)o = 60o45’ = 3645’

90,2o = 90(1/5)o = 90o12’ = 5412’

45,15o = 45(3/20)o = 45o9’ = 2709’

  a ) -2. ( x +6 ) + 6. ( x -10 ) =8

      -2.x + (-2).6 + 6x - 6.10 = 8

      -2x + (-12) + 6x -60 = 8

      (-2x+6x) + (-12) -60=8

      4x + ( -72)  = 8

      4x = 8 - ( -72 )

      4x = 8 + 72

      4x = 80

      x = 80 : 4

      x = 20

 ' * ' có nghĩ j z bạn

30,5 = 30°30'

60,75 = 60°45'

90,2 = 90°12'

45,15 = 45°9'

Xem lại dùm mink nha ! 

J=6 + 16 + 30 + 48 +...+ 19600 + 19998

Chia cả 2 vế cho 2 ta được

B/2 = 3 + 8 + 15 + 24 +  ......... + 98000+ 9999

B/2= 1x3+2x4+3x5+4x6+…….+98x100+99x101

B/2= 100/6[(100-1)x(2x100+1)] = 328350

-> B =328350x2=656700

K=2 + 5 + 9 + 14 + ....+ 4949 + 5049

Nhân cả 2 vế với 2 ta được

2xD=1x4+    2x5+ 3x6+   4x7+……..+98x101+99x102

2xD = 1(2+2)+2(3+2)+3(4+2)+...+99(100+2)

2xD = 1x2+1x2+2x3+2x2+3x4+3x2+...+99x100+99x2

2xD= (1x2+2x3+3x4+...+99x100)+2(1+2+3+...+99)

2xD =           333300       +                      9900        =      343200

 -> D= 343200 :2 =171600

\(\frac{2.4}{6.18}=\frac{1.2}{3.9}=\frac{2}{27}\)

\(\frac{3.5.7}{6.9.14}=\frac{1.5.7}{2.9.2}=\frac{35}{36}\)

\(\frac{4.7-4.5}{64}=\frac{4\left(7-5\right)}{64}=\frac{8}{64}=\frac{1}{8}\)

a, \(\frac{2.4}{6.18}\)

\(=\frac{2.2.2}{2.3.2.9}=\frac{2}{27}\)

P/s: Trl từng câu :)

điền mỗi số 1 cột

5! = 120

chắc chắn 1000 %

Nếu đúng thì k mik !!!

5!=1.2.3.4.5=120.

k nha

Ta có A=1+2012+2012²+...+2012⁷²

 A.2012=2012+2012²+...+2012⁷²+2012⁷³

 A.2012-A=(2012+2012²+...+2012⁷²+2012⁷³)-(1+2012+2012²+...+2012⁷²)

    A.2011=2012⁷³-1

   A=(2012⁷³-1):2011

  Vì 2012⁷³-1=2012⁷³-1 suy ra A<B

help me

A=1+2012+2012 mũ 2 + 2012 mũ 3+.............+2012 mũ 72

A=2012^0+2012^1+2012^2+....+2012^72

2012A=2012^1+2012^2+.....+2012^73

2012A-A=2012^73-1

A=(2012^73-1)/2011<2012^73-1