If `A+B+C=pi` then prove that `sum(tanA/(tanBtanC))=sumtanA-2sum cotA`

If A-B=pi/4 , then prove that: (1+tanA)

If A-B=pi/4 , then prove that: (1+tanA)(1-tanB)=2

If A+B = pi/4 , then prove that (1+tanA ) (1+tanB)=2 .

If A+B = (pi)/4 , then prove that (1+tanA)(1+tanB) = 2 .

If A+B=pi/4 , prove that: (1+tanA)(1+tanB)=2

If A+B+C=pi , Prove that tanA+tanB+tanC=tanA.tanB.tanC

prove that ((1-tanA)/(1-cotA))^2=tan^2A

If A+B+C= pi , prove that tan A+tan B+tan C= tanA tan B tan C

If A+B=pi//4 , then prove that (cotA-1)(cotB-1)=2

If A+B+C=pi, prove that (tanA)/(tanBdottanC)+(tanB)/(tanAdott a n C)+(tanC)/(tanAdottanB)=tanA+tanB+tanC-2cot A-2cot B-2cot C