a: 5A=5+5^2+...+5^2023

=>4A=5^2023-1

=>A=(5^2023-1)/4

b: 6B=6^2+6^3+...+6^41

=>5B=6^41-6

=>B=(6^41-6)/5

c: 16C=4^4+4^6+...+4^16

=>15C=4^16-4^2

=>C=(4^16-4^2)/15

d: 9D=3^3+3^5+...+3^27

=>8D=3^27-3

=>D=(3^27-3)/8

\(A=1+2+3+...+7+8=\dfrac{\left(8+1\right).\left(\dfrac{8-1}{1}+1\right)}{2}=36\)

\(B=3+4+5+...+10+11=\dfrac{\left(11+3\right).\left(\dfrac{11-3}{1}+1\right)}{2}=63\)

\(C=1+3+5+...+13+15=\dfrac{\left(15+1\right).\left(\dfrac{15-1}{2}+1\right)}{2}=64\)

\(D=2+4+6+...+18+20=\dfrac{\left(20+2\right).\left(\dfrac{20-2}{2}+1\right)}{2}=110\)

\(E=1+4+7+...+22+25=\dfrac{\left(25+1\right).\left(\dfrac{25-1}{3}+1\right)}{2}=117\)

\(G=1+5+9+...+33+37+41=\dfrac{\left(41+1\right).\left(\dfrac{41-1}{4}+1\right)}{2}=231\)

a,1-3+5-7+9-.......+33-35

=(1+5+9+....+33)-(3+7+11+...+35)

=153-171

=-18

Tick mk vài cái lên 300 mk giải nốt phần b

Tính thế đầy đủ các bước chưa b?

a) Đặt A=1-3+5-7+9-11+.......+33-35

Ta có: A=(1-3)+(5-7)+.........+(33-35)

=> A=(-2)+(-2)+.........+(-2)

            18 số hạng

=> A=(-2).18

=> A=-36

b) Đặt B= (42+43+44+45+36+47)-(32+33+34+35+36+37)

Ta có: B=(42-32)+(43-33)+(44-34)+(45-35)+(47-37)+(46-36)

=> B= 10+10+10+10+10+10

=> B=10.6

=> B=60

a) (3⁵ . 3⁷) : 3¹⁰ + 5 . 2⁴ - 7³ : 7

= 3¹² : 3¹⁰ + 5.16 - 7²

= 3² + 80 - 49

= 9 + 31

= 40

b) (7⁵ + 7⁹) . (5⁴ + 5⁶) . (3³.3 - 9²)

= (7⁵ + 7⁹) . (5⁴ + 5⁶) . (81 - 81)

= (7⁵ + 7⁹) . (5⁴ + 5⁶) . 0

= 0

=(33+47)+(35+45)+(37+43)+(39+41)
=80+80+80+80
=320

320 nhé !

giúp tớ với ah tớ cần gấp

`a)79+65 = 79 + (21+44)=(79+21)+44=100+44=144`

`b) 996 + 45 = 996+(41+4)=(996+4)+41=1000+41=1041`

`c) 37 + 198 = (35+2)+198=35+(2+198)=35+200 = 235`

`c) 3492 + 319 = 3492+(311+8)=(3492+8)+311=3500+311=3811`

a) 79+65=(79+21)+44=100+44=144

b) 996+45=(996+4)+41=1000+41=1041

\(3+3^3+3^5+3^7+...+3^{31}\)

\(=\left(3+3^3\right)+\left(3^5+3^7\right)+...+\left(3^{29}+3^{31}\right)\)

\(=\left(3+3^3\right)+3^4\left(3+3^3\right)+...+3^{28}\left(3+3^3\right)\)

\(=30\cdot\left(1+3^4+...+3^{28}\right)⋮30\)