`A=(\tan\alpha+\cot\alpha)^2-(\tan\alpha-\cot\alpha)^2`
`A=\tan^2\alpha+2.\tan\alpha.\cot\alpha-\tan^2\alpha+2.\tan\alpha.\cot\alpha-\cot^2\alpha`
`A=(\tan^2\alpha-\tan^2\alpha)+(\cot^2\alpha-\cot^2\alpha)+(2\tan\alpha\cot\alpha+2\tan\alpha\cot\alpha)`
`A=4\tan\alpha\cot\alpha`
`A=4.1`
`=4`