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主要内容

用三角函数求极限

问题

limit, start subscript, x, \to, start fraction, pi, divided by, 4, end fraction, end subscript, start fraction, cosine, left parenthesis, 2, x, right parenthesis, divided by, cosine, left parenthesis, x, right parenthesis, minus, sine, left parenthesis, x, right parenthesis, end fraction
选出正确答案:
不会做了?
不会做了?