正弦函数的平方乘以余弦函数，求这个函数在零到九十度的单调性，需要过程和答案，谢谢你们 正弦函数余弦函数的单调性怎么做
\u6b63\u5f26\u51fd\u6570\u4f59\u5f26\u51fd\u6570\u7684\u5355\u8c03\u6027\u4eb2\uff0c\u7f51\u53cb\uff0c\u60a8\u8bf4\u7684\u662f\u4e0d\u662f\u6b63\u5f26\u578by=Asin(\u03c9x+\u03c6\uff09\uff08A>0\uff0c\u03c9>0)\u7684\u5355\u8c03\u6027\u95ee\u9898\uff1a
\u7531\u4e8esinz\u5355\u8c03\u9012\u589e\u533a\u95f4\u662f[2k\u03c0-\u03c0/2\uff0c2k\u03c0+\u03c0/2]. k\u2208Z,
\u4ee4z=\u03c9x+\u03c6\uff0c
\u5219sin(\u03c9x+\u03c6\uff09\u7684\u5355\u8c03\u9012\u589e\u533a\u95f4\u662f2k\u03c0-\u03c0/2\u2264\u03c9x+\u03c6\u22642k\u03c0+\u03c0/2. k\u2208Z,
\u7531\u4e8esinz\u5355\u8c03\u9012\u51cf\u533a\u95f4\u662f[2k\u03c0+\u03c0/2\uff0c2k\u03c0+3\u03c0/2]. k\u2208Z,
\u4ee4z=\u03c9x+\u03c6\uff0c
\u5219sin(\u03c9x+\u03c6\uff09\u7684\u5355\u8c03\u9012\u51cf\u533a\u95f4\u662f2k\u03c0+\u03c0/2\u2264\u03c9x+\u03c6\u22642k\u03c0+3\u03c0/2. k\u2208Z,
\u4eb2\uff0c\u89e3\u51fax\u5f97\u5355\u8c03\u533a\u95f4.
\u4f59\u5f26\u578b\u4e5f\u5982\u6b64
\u795d\u60a8 \u5b66\u4e1a\u6709\u6210 \u5feb\u4e50\u76c8\u95e8 \uff01
按复合函数同增异减来做，如下详解，望采纳
过程如图，
绛旓細鎸夊鍚堝嚱鏁板悓澧炲紓鍑忔潵鍋锛屽涓嬭瑙ｏ紝鏈涢噰绾
绛旓細绛旀濡傚浘
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