tan^2乘x的导数是多少?
(tan^2x)’
=tanxtanx
=tanx(tanx)’+(tanx)’tanx
=2tanx(tanx)’
=2tanxsec^2x
(xtan^2x)’
=x(tan^2x)’+x’tan^2x
=2xtanxsec^2x+tan^2x
(tan^2x)’
=tanxtanx
=tanx(tanx)’+(tanx)’tanx
=2tanx(tanx)’
=2tanxsec^2x
(xtan^2x)’
=x(tan^2x)’+x’tan^2x
=2xtanxsec^2x+tan^2x
在平面当中有四条,线段两边各一条,交叉于线段的两条.在三维空间中就会有无数条了.