积分上限π/4,积分下限0,tan^3xdx的定积分的解答过程答:∫[0,π/4] (tanx)^3dx=∫[0,π/4][(secx)^2-1]tanxdx=∫[0,π/4](secx)^2tanxdx -∫[0,π/4]tanxdx=∫[0,π/4]tanxdtanx +∫[0,π/4]dcosx/cosx=(1/2)tanx|[0,π/4] +ln|cosx| |[0,π/4]=1/2+lncos(π/4)
积分上限π/4,积分下限0,tan^3xdx的定积分的解答过程答:∫[0,π/4] (tanx)^3dx =∫[0,π/4][(secx)^2-1]tanxdx =∫[0,π/4](secx)^2tanxdx -∫[0,π/4]tanxdx =∫[0,π/4]tanxdtanx +∫[0,π/4]dcosx/cosx =(1/2)tanx|[0,π/4] +ln|cosx| |[0,π/4]=1/2+lncos(π/4)