`tan((pi)/(2)-cot^(-1).(1)/(3))=`

Prove that: tan^(-1)(1)/(7)+tan^(-1)(1)/(13)=tan^(-1)(2)/(9)tan^(-1)+tan^(-1)(1)/(5)+tan^(-1)(1)/(8)=(pi)/(4)tan^(-1)(3)/(4)+tan^(-1)(3)/(5)-tan^(-1)(8)/(19)=(pi)/(4)tan^(-1)(1)/(5)+tan^(-1)(1)/(7)+tan^(-1)(1)/(3)+tan^(-1)(1)/(8)=(pi)/(4)cot^(-1)7+cot^(-1)8+cot^(-1)18=cot^(-1)(1)/(13)

cot{ (2019pi)/(2) - ( cosec^(-1) (5)/(3) + tan^(-1)"" (2)/(3) ) } = .....

The solution set of inequality (cot^(-1)x)(tan^(-1)x)+(2-(pi)/(2))cot^(-1)x-3tan^(-1)x-3(2-(pi)/(2))>0 is (a,b), then the value of cot ^(-1)a+cot^(-1)b is

tan^(-1)((2x)/(1-x^2))+cot^(-1)((1-x^2)/(2x))=pi/3

Find the value of tan^(-1) (-tan((13pi)/(8)))+ cot^(-1) (-cot((19pi)/(8)))

Find the value of tan^(-1)(-1/(sqrt(3)))+cot^(-1)((1)/(sqrt(3))) + tan^(-1)[sin((-pi)/(2))] .

Find the value of tan^(-1)(-1/(sqrt(3)))+cot^(-1)((1)/(sqrt(3))) + tan^(-1)[sin'((-pi)/(2))] .

Find the value of tan (pi/4+2cot^(-1) sqrt3)

tan^(-1)(-5)+cot^(-1)(-5)=(pi)/2