If A+B +C =180∘, then ∑tanA2tanB2 is equal
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Given that, A + B + C =180∘
⇒A2+B2=90∘−C2⇒tan(A2+B2)=tan(90∘−C2)⇒(tanA2+tanB2)tanC2=1−tanA2tanB2⇒tanA2tanB2+tanB2tanC2+tanC2tanA2=1
ca+b=1−tan(A2)tan(B2)1+tan(A2)tan(B2)
If tan A=2tanB+cotB, then 2tan(A-B)=