sinx从0到π定积分是多少 sinx在0到派的定积分为什么不是0
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\u51fd\u6570\u53ef\u4ee5\u5b58\u5728\u4e0d\u5b9a\u79ef\u5206\uff0c\u800c\u4e0d\u5b58\u5728\u5b9a\u79ef\u5206\uff1b\u4e5f\u53ef\u4ee5\u5b58\u5728\u5b9a\u79ef\u5206\uff0c\u800c\u4e0d\u5b58\u5728\u4e0d\u5b9a\u79ef\u5206\u3002
\u8fde\u7eed\u51fd\u6570\u4e00\u5b9a\u5b58\u5728\u5b9a\u79ef\u5206\u548c\u4e0d\u5b9a\u79ef\u5206\uff1b\u82e5\u53ea\u6709\u6709\u9650\u4e2a\u95f4\u65ad\u70b9\uff0c\u5219\u5b9a\u79ef\u5206\u5b58\u5728\uff1b\u82e5\u6709\u8df3\u8dc3\u95f4\u65ad\u70b9\uff0c\u5219\u539f\u51fd\u6570\u4e00\u5b9a\u4e0d\u5b58\u5728\uff0c\u5373\u4e0d\u5b9a\u79ef\u5206\u4e00\u5b9a\u4e0d\u5b58\u5728\u3002
\u6269\u5c55\u8d44\u6599\uff1a
\u628a\u51fd\u6570\u5728\u67d0\u4e2a\u533a\u95f4\u4e0a\u7684\u56fe\u8c61[a,b]\u5206\u6210n\u4efd\uff0c\u7528\u5e73\u884c\u4e8ey\u8f74\u7684\u76f4\u7ebf\u628a\u5176\u5206\u5272\u6210\u65e0\u6570\u4e2a\u77e9\u5f62\uff0c\u518d\u6c42\u5f53n\u2192+\u221e\u65f6\u6240\u6709\u8fd9\u4e9b\u77e9\u5f62\u9762\u79ef\u7684\u548c\u3002
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\u5404\u5e38\u6570\u503c\u5bf9\u51fd\u6570\u56fe\u50cf\u7684\u5f71\u54cd\uff1a
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A\uff1a\u51b3\u5b9a\u5cf0\u503c\uff08\u5373\u7eb5\u5411\u62c9\u4f38\u538b\u7f29\u7684\u500d\u6570\uff09
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\u4f60\u8fd9\u6362\u5143\u6cd5\u6709\u95ee\u9898
\u6362\u5143\u7684\u65f6\u95f4,\u533a\u95f4\u8981\u4e00\u4e00\u5bf9\u5e94,\u800csinx\u57280\u5230\u03c0\u4e0d\u662f\u5355\u8c03\u51fd\u6570,\u6240\u4ee5\u4f60\u7684\u6362\u5143\u672c\u8eab\u5c31\u662f\u9519\u8bef\u7684.
在草稿本上列的，比较详细了吧
sinx从0到π/2的积分是1，从0到π是2
Ssinxdx从0到π
=-Sdcosx从0到π
=-cosx从0到π
=-(cosπ-cos0)
=2
∫(0,π)sinxdx=∫(0,π/2)sinxdx+∫(π/2,π)sinxdx=∣cos(π/2)-cos0∣+∣cos(π)-cos(π/2)∣=2
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绛旓細sinx鍦0鍒跋鐨勯潰绉槸2銆傚垎鏋愯繃绋嬪涓 闈㈢Н=鈭玔0锛毾]sinxdx =-cosx|[0锛毾]=-(cos蟺 -cos0)=-(-1-1)=2 x鈭圼0锛屜]锛宻inx涓巟杞村洿鎴愮殑闈㈢Н涓2銆
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绛旓細绉垎涓婇檺涓2蟺,涓嬬嚎涓0,锛堢敱浜庢湰浜轰笉浼氳緭杩欑绗﹀彿,涓浠ヤ笅鐪佺暐锛夆埆 sinxdx=[-cosx]=-cos2蟺+cos0=-1+1=0
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