23 March 2020 Sergiu Funieru The formula for tan (-a) [formula for the tangent of minus a] 0 The formula for tan (-a) [formula for the tangent of minus a] Have you seen this? 0
![The formula for tan (-a) [formula for the tangent of minus a]](https://lunlun.com/wp-content/uploads/2020/03/LL_1589-The-formula-for-tan-a-formula-for-the-tangent-of-minus-a.png "The formula for tan (-a) [formula for the tangent of minus a]")