(3x-16). 7 mũ 5 = 2. 7 mũ 6 . 1
\(A=5+5^2+5^3+5^4+...+5^{2004}\)
\(B=7^1+7^2+7^3+...+7^{2015}\)
\(C=4^5+4^6+4^7+...+4^{2016}\)
Tính:
a)1*4*7+4*7*10+7*10*13+....+100*103*106
b)1*4+4*7+7*10+.....+100*103
c)1*1*1+4*4*4+7*7*7+....+99*99*99
d)1*3*3*3+3*5*5*5+5*7*7*7+.....+49*51*51*51
e)1*99+2*98+3*97+......+50*50
f)1*99+3*97+5*95+....+49*51
Giúp mình nhé!
a) ( 519 : 517 +3 ) : 7
b) 79 : 77 - 32 + 23 . 52
c) 1200 : 2 + 62 . 21 + 18
d) 59 : 57 + 70 : 14 - 20
e) 100 : 52 + 7.32
f) 84 : 4 +39 : 37+ 50
g) 32.5 - 22.7 + 83
h) 59 : 57 + 12.3 + 70
i) 5.22 + 98 : 72
(7^2021 - 5. 7^2020) : 7^2019
a, (4/5)2x+7= 625/256
b, 7x+2 +7x+1 + 7x / 57 = 52x + 2x+1 + 52x+3 / 131
Bài 1: Chứng minh rằng:
a, 5^5 - 5^4 + 5^3 chia hết cho 7.
b, 7^6 + 7^5 - 7^4 chia hết cho 11.
c, 10^9 + 10^8 + 10^7 chia hết cho 222.
d, 10^6 - 5^7 chia hết cho 59.
e, 3^n+2 - 2^n+2 + 3^n - 2^n chia hết cho 10 với n \(\in\) N*.
f, 81^7 - 27^9 - 9^13 chia hết cho 45.
7^6+7^5-7^4 chia hết cho 55
16^5+2^15 chia hết cho 33
81^7-27^9-9^13 chia hết cho 404
A. 7⁸÷7⁵-11² B. 3⁴.3-5¹⁶÷5¹³+2023⁰.12² C. 4³÷4-2².3+5².3 D. 2015⁰.14+3².2-5¹⁰÷5⁸
tim x thuoc N
a,\(21x-1⋮11\)
b,\(5x+1⋮7\) va x la STN lon nhat co 3 chu so
c,\(3x-2⋮11\) va \(100< x< 2017\)
d,\(5⋮\left(x-3\right)\)
e,\(\left(3x+2\right)⋮\left(x+1\right)\)