(1)tan（a-p）=(tana-tanp)/(1+tanatanp)
tana-tanp=2+1/3=7/3
tanatanp=2*(-1/3)=-2/3
tan（a-p）=(tana-tanp)/(1+tanatanp)
=7/3/(1-2/3)=7
(2)tan(a+p)
=(tana+tanp)/(1-tanatanp)
=5/3/(1+2/3)=1
0
已知tana=2,tanp=-1/3,其中0
(1)tan（a-p）=(tana-tanp)/(1+tanatanp)
tana-tanp=2+1/3=7/3
tanatanp=2*(-1/3)=-2/3
tan（a-p）=(tana-tanp)/(1+tanatanp)
=7/3/(1-2/3)=7
(2)tan(a+p)
=(tana+tanp)/(1-tanatanp)
=5/3/(1+2/3)=1
0