A. only I is true
B. only II is true
C. both I,II are true
D. neither I and II is true
In ΔABC, if cos A cos B +sin A sin B sin C =1, then a:b:c =
If 4,5 are two sides of a triangle and the included angle is 600, then is area is
In ΔABC, if r1 =3, r2= 10, r3= 15, then c=
.In ΔABC, if 2R+ r= r1, then the triangle isa
If sin(y+z-x),sin(z+x-y), sin(x+y-z) are in A.P then tan x, tan y, tan z are in
If Two angles of a triangle are 300, 450 and the included side is √3+1, then the remaining sides are
In ΔABC, if (a+b-c) (a+b-c) = 3ab, then C =
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