1. 1 b = 6. a = b = 3) 2 4) 6. 2 1- -1 tan cos + tan 7. The value of 6 7 16 A) 17 B) 16 C) 7 D) none of these 7. D sin u (Ncosa+1)+ cot"(Vecos a+1)=u (where tan cos a a + nn + 8. If ), then is equal to tan? a tan 2a sec? a tan a Cos? a D) A) ) C) 2/3 9. If cot"x+ cor"!y+cotrz=x. y, 2>0 and xy < 1, then x +y+z is also equal to 1 1 1 a -+-+- X y z c. xy + yz + zx b xy: d none of these 10. If tanx+ tan y+ tanz= then a x+y+z-xyz -0 bx+y+z+xyz =0 c. xy+yr + zx + 1-0 d xy + yz + zx-1=0 11. If0