Question

Question #5221c

Answer 1

`tan2x=-(4sqrt21)/17`

Explanation:

Given `secx=-5/2`, `tanx =sqrt(sec^2x-1)=sqrt((-5/2)^2-1)=sqrt21/2`

Now, using the double angle formula for `tan2x`, we can say:

`tan2x=(2tanx)/(1-tan^2x)=(2(sqrt21)/2)/(1-((sqrt21)/2)^2)=sqrt21/(-17/4)=`
`-(4sqrt21)/17`