meili 发表于 2022-10-27 15:46:01

y=2xsin(2x+5)求导数y#39;=(2x)#39;sin(2x+5)+(2x)[sin(2x+5)]#39;=2sin(2x+5)+2xcos(2x+5)可答案是2sin(2x+5)+4xcos(2x+5)哪里错了

<p>问题:y=2xsin(2x+5)求导数y#39;=(2x)#39;sin(2x+5)+(2x)#39;=2sin(2x+5)+2xcos(2x+5)可答案是2sin(2x+5)+4xcos(2x+5)哪里错了
<p>答案:↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">李唐的回答:<div class="content-b">网友采纳  解析  y'=(2x')sin(2x+5)+2xsin(2x+5)'  =2sin(2x+5)+2x*2*cos(2x+5)  =2sin(2x+5)+4xcos(2x+5)  因为你没有对2x+5求导  它是复合的<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">安德玺的回答:<div class="content-b">网友采纳  求了之后变成【2sinu+2xcosu】·2=4sin(2x+5)+4xcos(2x+5)还是没有算出<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">李唐的回答:<div class="content-b">网友采纳  先是对2x求导的是2不要对sin(2x+5)求导第一部错了的
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查看完整版本: y=2xsin(2x+5)求导数y#39;=(2x)#39;sin(2x+5)+(2x)[sin(2x+5)]#39;=2sin(2x+5)+2xcos(2x+5)可答案是2sin(2x+5)+4xcos(2x+5)哪里错了