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\(C_5^0 + C_5^1 + C_5^2 + C_5^3 + C_5^4 + C_5^5\) ;
参考答案:\(32\),
\(C_5^0 + C_5^1 + C_5^2 + C_5^3 + C_5^4 + C_5^5 \)
\(= 2\left( {C_5^0 + C_5^1 + C_5^2} \right) \)
\(= 2\left( {C_6^1 + C_5^2} \right) \)
\(= 2 \times \left( {6 + \frac{{5 \times 4}}{{2 \times 1}}} \right) \)
\(= 32\)(或原式\( = {2^5} = 32\));