题目

计算下列各小题 (1) ; (2) . 答案: 解: 2cos245°+tan60°·tan30°−cos60° = 2×(22)2+3×33−12 = 2×12+33−12=1+1−12=32 . 解: 3tan30°+8cos45°+(1−tan60°)2 = 3×33+8×22+(1−3)2 = 3+8×22+(3−1) = 3+42+3−1=23+1 .
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