sinxcosx=2/5,且根号下cosx^2=-cosx,求,tanx+1/tanx=?

问题描述:

sinxcosx=2/5,且根号下cosx^2=-cosx,求,tanx+1/tanx=?

原式=sinx/cosx+cosx/sinx
=(sin²x+cos²x)/sinxcosx
=1/(2/5)
=5/2