\(99\cdot100\cdot99:2-98\cdot99\cdot100:3\)
\(=99\cdot99\cdot50-98\cdot33\cdot100\)
\(=33\cdot50\left(99\cdot3-98\cdot2\right)\)
\(=33\cdot50\cdot\left(297-196\right)\)
\(=1650\cdot101=166650\)
Tính:(101+100+99+98+...+3+2+1)/(101-100+99-98+...+3-2+1)
C=1/100 - 1/100*99 - 1/99*98 - 1/98*97 - . . . -1/3*2 - 1/2*1
tính: B=1+2+3.............+98+99
giải
B=1+2+3+......+98+99
+
B=99+98+.....+2+1
2B=100+100+...+100+100 = 100.99 = B = 50.99=4950
1/1*2 - 1/2*3 - 1/3*4- ..... -1/98*99=1/100+1/99*100
1/1*2 1/2*3 1/3*4 ..... -1/98*99=1/100 1/99*100
Tính A=\(\frac{101+100+99+98+...+3+2+1}{101-100+99-98+...+3-2+1}\)
2^100-2^99+2^98-2^97+...+2^2-2
3^100-3^99+3^98-3^97+...+3^2-3+1
Giúp với các bạn ơi!!!
Tính nhanh :
1/100-1/100×99-1/99×98-...-1/3×2 -1/2×1
Tính:
a) A=2^100 - 2^99 + 2^98 - 2^97 + ... + 2^2 - 2
b) B=3^100 - 3^99 + 3^98 - 3^97 + ... + 3^2 - 3
a)A=1-2+3-4+...+99-100
b)B=1-2-3+4+5-6-7+...+97-98-99+100
c)C=2100-299s-998-...-22-2-1
giup mik vs a
