\(166.\left(-127+234\right)-234.\left(166+127\right)\)
\(=\)\(166.107-234.293\)
\(=\)\(17762-68562\)
\(=\)\(-50800\)
\(53.39+47.39-53.21-47.21\)
\(=\)\(39.\left(53+47\right)-21.\left(53+47\right)\)
\(=\)\(39.100-21.100\)
\(=\)\(100.\left(39-21\right)\)
\(=\)\(100.18\)
\(=\)\(1800\)
tính nhanh:166.[-127+234]-234.[166+127]
166 * ( – 127 + 234 ) – 234 * ( 166 +127 )
tính nhanh a / 166 * ( – 127 + 234 ) – 234 * ( 166 +127 )
b / 53 * 39 + 43 * 39 – 53 * 21 – 47 * 21
Tính : B=53.39+47.39-53.21-47.21
53.39+47.39-53.21-47.21
53.39+47.39-53.21-47.21
53.39-47.39-53.21-47.21
tinh nhanh:53.39+47.39-53.21-47.21
Tính :a,1+(-3)+5+(-7)+...+72 b, 53.39+47.39-53.21-47.21
