∫(sinx)^2/[1+e^(-x)] dx 积分上下限(π/4,π/4)怎么算?
来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/24 02:18:26
∫(sinx)^2/[1+e^(-x)]dx积分上下限(π/4,π/4)怎么算?∫(sinx)^2/[1+e^(-x)]dx积分上下限(π/4,π/4)怎么算?∫(sinx)^2/[1+e^(-x)]
∫(sinx)^2/[1+e^(-x)] dx 积分上下限(π/4,π/4)怎么算?
∫(sinx)^2/[1+e^(-x)] dx 积分上下限(π/4,π/4)怎么算?
∫(sinx)^2/[1+e^(-x)] dx 积分上下限(π/4,π/4)怎么算?
注:此题的上下限有错,应该是积分上下限(-π/4,π/4)!
原式=∫(-π/4,π/4)(sinx)^2/[1+e^(-x)]dx (∫(-π/4,π/4)表示从-π/4到π/4积分)
=∫(-π/4,0)(sinx)^2/[1+e^(-x)]dx+∫(0,π/4)(sinx)^2/[1+e^(-x)]dx
=-∫(π/4,0)(sinx)^2/(1+e^x)dx+∫(0,π/4)(sinx)^2/[1+e^(-x)]dx (第一个积分用-x代换x得)
=∫(0,π/4)(sinx)^2/(1+e^x)dx+∫(0,π/4)e^x(sinx)^2/(1+e^x)dx (第二个积分分子分母同乘e^x得)
=∫(0,π/4)(1+e^x)(sinx)^2/(1+e^x)dx
=∫(0,π/4)(sinx)^2dx
=1/2∫(0,π/4)[1-cos(2x)]dx ()
=1/2[x-1/2sin(2x)]|(0,π/4)
=1/2(π/4-1/2)
=(π-2)/8
上下限相等? 那不就是零么
如果是正负的话,那个,我也算不出来...用软件计算出来约等于 0.14...
所以猜测答案是 pi-3 ,哈哈
求不定积分:1.∫e^(sinx)[x(cosx)^3-sinx]/(cosx)^2dx 2.∫[e^(3x)+e^x]/[e^(4x)-e^(2x)+1]dx
∫(x/2+e^x+sinx)dx
lim(x+e^2x)^(1/sinx)
∫ e^2x sinx dx ..
∫e^x(sinx)^2dx
lim (e^x-sinx-1)/(arcsinx^2)
∫e^x乘以cosxdx=1/2×e^x(sinx+cosx)+C如何得到的
∫[e^sin2x*(sinx)^2]/e^2x dx
e^x(sinx)^2不定积分
limx→0 (e^x-1)x^2/x-sinx
∫(-1,1)[e^(-x^2)[in(x+1)/(x-1)]+cosx(sinx)^2]dx=
lim((e^2-1-x)^2)/(x(sinx^3))
lim(x-->0) (e^(2x)-1)/sinx
(1+2x)^(3/sinx)=e^{[ln(1+2x)](3/sinx)}怎么得到的,
∫(x sinx)e^x dx
高数求极限题目x->0 lim{[2+e^(1/x)]/(1+e^(4/x)} + sinx/|x|
X趋近于0.求(e^x-e^sinx)/[x^2*ln(1+x)]的极限值.
lim (e^sinx-e^x)/(sinx-x)