(1+tanA)(1+tanB)=2
展开有:1+tanA+tanB+tanA*tanB=2
化简:
tanA+tanB+tanA*tanB=1
tanA+tanB=1-tanA*tanB
(tanA+tanB)=(1-tanA*tanB)
(tanA+tanB)/(1-tanA*tanB)=1
tan(A+B)=1
A+B=45
C=135
(1+tanA)(1+tanB)=2
展开有:1+tanA+tanB+tanA*tanB=2
化简:
tanA+tanB+tanA*tanB=1
tanA+tanB=1-tanA*tanB
(tanA+tanB)=(1-tanA*tanB)
(tanA+tanB)/(1-tanA*tanB)=1
tan(A+B)=1
A+B=45
C=135