Bài làm:

a) \(a=2+2^3+2^5+...+2^{99}+2^{101}\)

\(\Rightarrow4a=2^3+2^5+2^7+...+2^{101}+2^{103}\)

\(\Rightarrow4a-a=\left(2^3+2^5+2^7+...+2^{103}\right)-\left(2+2^3+2^5+...+2^{101}\right)\)

\(\Leftrightarrow3a=2^{103}-2\)

\(\Rightarrow a=\frac{2^{103}-2}{3}\)

Vậy \(a=\frac{2^{103}-2}{3}\)

b) \(b=1-5^3+5^6-5^9+...+5^{96}-5^{99}\)

\(\Rightarrow125b=5^3-5^6+5^9-5^{12}+...+5^{99}-5^{102}\)

\(\Rightarrow125b+b=\left(5^3-5^6+5^9-5^{12}+...+5^{99}-5^{102}\right)+\left(1-5^3+5^6-5^9+...+5^{96}-5^{99}\right)\)

\(\Leftrightarrow126b=1-5^{102}\)

\(\Rightarrow b=\frac{1-5^{102}}{126}\)

Vậy \(b=\frac{1-5^{102}}{126}\)

Học tốt!!!!

a,\(5^3.2-100:4+2^3.5\)

= 125 . 2 - 25 + 8 . 5

= 250 - 25 + 40

= 265

b, \(6^2:9+50.2-3^3.3\)

= 36 : 9 + 100 - 27 . 3

= 4 + 100 - 81

= 23

bạn kia ko làm các ý khác à

b) \(5^3\cdot2-100:4+2^3\cdot5\)

\(=125\cdot2-25+8\cdot5\)

\(=250-25+40\)

\(=225+40=265\)

c) \(6^2:9+50\cdot2+3^3-3\)

\(=36:9+100+27-3\)

\(=4+100+27-3\)

\(=104+27-3=131-3=128\)

d) \(3^2\cdot5+2^3\cdot10-81:3\)

\(=9\cdot5+8\cdot10-27\)

\(=45+80-27\)

\(=125-27=98\)

e) \(5^{13}:5^{10}-25\cdot2^2\)

\(=5^{13-10}-5^2\cdot2^2\)

\(=5^3-\left(5\cdot2\right)^2\)

\(=125-10^2\)

\(=125-100=25\)

f) \(20:2^2+5^9:5^8\)

\(=20:4+5^{9-8}\)

\(=5+5^1=5+5=10\)

g) \(100:5^2+7\cdot3^2\)

\(=10^2:5^2+7\cdot9\)

\(=\left(10:5\right)^2+63\)

\(=2^2+63=4+63=67\)

h) \(84:4+3^9:3^7+5^0\)

\(=21+3^{9-7}+1\)

\(=21+3^2+1\)

\(=21+9+1=30+1=31\)

i) \(29-\left[16+3\cdot\left(51-49\right)\right]\)

\(=29-\left[16+3\cdot2\right]\)

\(=29-\left[16+6\right]\)

\(=29-22=7\)

j) \(\left(15^{19}:5^{17}+3\right)\cdot0:7\)

\(=\left[\left(3\cdot5\right)^{19}:5^{17}+3\right]\cdot0\)

Vì số nào nhân cho 0 cũng bằng 0 nên giá trị biểu thức trên bằng 0

k) \(7^9:7^7-3^2+2^3\cdot5\)

\(=7^{9-7}-9+8\cdot5\)

\(=7^2-9+40\)

\(=49-9+40=40+40=80\)

l) \(1200:2+6^2\cdot2^1+18\)

\(=600+36\cdot2+18\)

\(=600+72+18\)

\(=600+\left(72+18\right)=600+90=690\)

m) \(5^9:5^7+70:14-20\)

\(=5^{9-7}+5-20\)

\(=5^2+5-20\)

\(25+5-20=30-20=10\)

Những câu sau mình làm sau nhé bạn!!!!!!!

C=1+\(5^{3^{ }}+5^6+...+5^{99}\)

\(5^3\)C=\(5^3+5^6+...+5^{99}+5^{102}\)

(\(5^3-1\))C=\(5^{102}-1\)

C=\(\frac{5^{102}-1}{124}\)

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    A  = 2 +  2² + 2³ +...+2⁹⁹ + 2¹⁰⁰

   2A  =       2² + 2³ +...+ 2⁹⁹ + 2¹⁰⁰ + 2¹⁰¹

2A - A =      2¹⁰¹ - 2

   A      = 2¹⁰¹ - 2

  B        =  1 + 5 + 5² + 5³ +...+ 5⁹⁹ + 5¹⁰⁰

5B        =       5 + 5² + 5³ +...+ 5⁹⁹ + 5¹⁰⁰ + 5¹⁰¹

5B - B   =  5¹⁰¹ - 1

   4B     = 5¹⁰¹ - 1

     B      = \(\dfrac{5^{101}-1}{4}\)

     B     = 

a: =5-78*32

=5-2496

=-2491

b: \(=6\left(9-6\right)=6\cdot3=18\)

c: \(=46\cdot\dfrac{\left(123-42\right)}{81}=46\)

d: \(=181+3-84+8\cdot25\)

=100+200

=300

e: \(=64\cdot35+140\cdot84-1=2240-1+11760\)

=14000-1

=13999

f: \(=3^3+25\cdot8-1=26+200=226\)

g: \(=3+2^4+1=16+4=20\)

h: \(=36:4\cdot3+2\cdot25-1=27+50-1=27+49=76\)

\(A=4+4^2+...+4^{99}\)

\(\Rightarrow4A=4^2+3^3+...+4^{99}+4^{100}\)

\(\Rightarrow4A-A=4^{100}-4\)

\(\Rightarrow3A=4^{100}-4\Rightarrow A=\frac{4^{100}-4}{3}\)

\(B=5+5^2+...+5^{10}\)

\(5B=5^2+5^3+...+5^{10}+5^{11}\)

\(5B-B=4B=5^{11}-5\Rightarrow B=\frac{5^{11}-5}{4}\)

C đang 6 mũ sao tự nhiên nhảy đâu ra 9 mũ?

Nếu nó là 6 mũ thì làm tương tự như 2 câu trên

Ai đó help me mai lộp rồi

A = 2^3 + 2^4+ 2^5+ 2^6 + 2^7 + ... + 2^90 

2A = 2^4 + 2^5 + 2^6 + 2^7 + 2^8 + .... + 2^90 + 2^100

2A - A = ( 2^4 + 2^5 + 2^6 + 2^7 + 2^8 + .... + 2^90 + 2^100 ) - (  2^3 + 2^4+ 2^5+ 2^6 + 2^7 + ... + 2^90 ) 

A = 2^100 - 2^3 

B = 1 + 5 + 5^2 + 5^3 + 5^4 + .... + 5^50 

5B = 5 + 5^2 + 5^3 + 5^4 + 5^5 + .... + 5^50 + 5^51 

5B - B = ( 5 + 5^2 + 5^3 + 5^4 + 5^5 + .... + 5^50 + 5^51 ) - ( 1 + 5 + 5^2 + 5^3 + 5^4 + .... + 5^50 )

4B = 5^51 - 1 

B = 5^51 - 1 / 4