\(50^2-18^2+32^2+100\cdot32\)
\(=\left(32^2-18^2\right)+\left(50^2+100\cdot32\right)\)
\(=\left(32+18\right)\left(32-18\right)+50\cdot\left(50+2\cdot32\right)\)
\(=50\cdot14+50\cdot114\)
\(=50\cdot128\)
\(=6400\)
\(50^2-18^2+32^2+100\cdot32\)
\(=\left(32^2-18^2\right)+\left(50^2+100\cdot32\right)\)
\(=\left(32+18\right)\left(32-18\right)+50\cdot\left(50+2\cdot32\right)\)
\(=50\cdot14+50\cdot114\)
\(=50\cdot128\)
\(=6400\)
1+2+3+....+49/501+502+...549
Hoá học nha
502 + 4P = ?
d) \(5x-3.\left\{4x-2.\left[4x-3.\left(5x-2\right)\right]\right\}=182\)
\(\Leftrightarrow5x-3.\left[4x-2.\left(4x-15x+6\right)\right]=182\)
\(\Leftrightarrow5x-3.\left[4x-2.\left(-11x+6\right)\right]=182\)
\(\Leftrightarrow5x-3.\left(4x+22x-12\right)=182\)
\(\Leftrightarrow5x-3.\left(26x-12\right)=182\)
\(\Leftrightarrow5x-78x+35=182\)
\(\Leftrightarrow-73x+36=182\)
\(\Leftrightarrow-73x=146\)
\(\Leftrightarrow x=-2\)
Tính nhanh:
a) 73 2 - 27 2 ; b) 36 2 - 14 2 ;
c) 63 2 - 27 2 + 72 2 - 18 2 ; d) 54 2 + 82 2 - 18 2 - 46 2 .
giúp mìk vs : c/m: (x^2011+x^2010+....+x+1) chia hết (x^502+x^501+...+x+1)
tính nhanh
a)A=54.34-(152-1)(152+1)
b)C=502-492+482-472+...+22-12
Rút gọn biểu thức: 3 2 2 + 1 2 4 + 1 2 8 + 1 2 16 + 1
Tìm số tự nhiên n thõa mãn
1/2*4+1/4*6+1/6*8+.............+1/2n(2n+2)=502/2009
Tìm chữ số tận cùng của tổng S = 21 + 35 + 49 + ... + 5022001 .