求证:(tan a*sin a)/(tan a-sin a)=(tan a+sin a)/(tan a*sin a)

求证:(tan a*sin a)/(tan a-sin a)=(tan a+sin a)/(tan a*sin a) 求证tan^2asin^2a=tan^2a-sin^2a求证tan^2 a 乘 sin^2 a=tan^2 a-sin^2 a 已知角A角B角C是三角形ABC的内角,求证,tan(A/2)*tan(B/2)+tan(B/2)*tan(C/2)+ta 求证:sin a(1+tan a)+cos a(1+1/tan a)=1/sin a+1/cos a 求证 cos^2 a-sin^2 a/1-2sin acos a =1+tan a/1-tan a 求证：tan a/2＝(1-cos)/sin a=sin a/(cos a+1) 求证sin与tan 已知3sinB=sin(2A+B),求证tan(A+B)=2tanA 2.求证：tan a的平方乘以sin a的平方=tan a的平方-sin a的平方. 已知 3sin A = sin (2B +A ),求证 ： tan（A+B)= 2tanB 已知sin(a+β)=1,求证;tan(2a+3β)-tanβ=0 已知3sinβ=sin(2a+β)求证tan(a+β)=2tan a 求证恒等式：（tan a+sec a-1)/(tan a -sec a+1)=（1+sin a）/cos a 求证 sin~4a-cos~4a=sin~2a-cos~2a tan~2asin~2a=tan~2a-sin~2a 已知3sin b=sin(2a+b) 求证tan(a+b)=2tana 求解 已知 sin(a+b)=1/2 ,sin(a_b)=1/3,求证:tan a=5tan b求解:已知 sin(a+b)=1/2 ,sin(a_b)=1/3,求证:tan a=5tan b 已知tan^2 a=2tan^ B +1,求证sin^2 b=sin^2 a -1 已知tan^2A=2tan^B+1求证sin^2B=2sin^2A-1救急 已知tan^2a=2tan^2b+1,求证:sin^b=2sin^2a-1