tinh nhanh: 1+1/2(1+2)+1/3(1+2+3)+1/4(1+2+3+4)+...+1/10(1+2+3+...+20)
Tinh: A= 102 - (52 . 4 - 43 . 3) + 23 ket qua phep tinh ?
bai 1: Tinh D=3/1^2*2^2 + 5/2^2*3^2 +7/3^2*4^2 + ... +19/9^2*10^2
tinh
a, 2^3+5^2+4^2-5^3
b,4^3.57+4^3.53-4^3.10
c, (2^6.15+2^6.86-2^6):64
d, (10^2-1):(10^2-2):(10^2:3) co 100 thua so
1) Thuc hien phep tinh:
a) 4^6 × 9^2 / 6^3 × 8^2
b) 5^6 × 15^4 /5^4 × 3^3
c) 3^9 - 2^3 × 3^7 + 2^10 × 3^2 - 2^13 / 3^10 - 2^2 × 3^7 + 2^10 × 3^3 - 2^12
d) (1/9)^10 : (1/3)^20
e) (1/64)^5 × (1/4)^7
2) Chung minh rang:
a)2014^100+2014^99 chia het cho 2015
b) 4^13+32^5-8^8 chia het cho 5
c) 81^27-27^9-9^13 chia het cho 405
Help me!! Pleass!!
Tinh:
A= (10^3-1}^1.(10^3-2)^2.(10^3-3)^3.........(10^3-100)^100
Tinh:1-2-3-4-5-6-7-8-9-10-...543+1+2+3+4+5+....188 = ?
tinh gia tri bieu thuc C= hon so 5 va 9 phan 10 chia 3 phan 2 - { 2 va 1 phan 3 nhan 4 va 1 phan 2 - 2 nhan 2 va 1 phan 3 } chia 7 phan 4
tinh nhanh A = 1*2+2*3+3*4+4*5+5*6+6*7+7*8+8*9+9*10
