Solving this trigo Question ?

• Isis

  2 Nov 07, 11:18

  How do you solve this Trigo problem?
  
  Can (1-cosx)/sinx be = tan(x/2)
  
  
• eagle

  2 Nov 07, 11:21

  1 - cos x = 2 ( sin (x/2) )^2 ----- (1)
  sinx = 2 sin (x/2) cos (x/2) ------ (2)
  
  dividing (1) / (2) gives you tan (x/2)
• Isis

  2 Nov 07, 12:39

  Can (tanx/2 sinx/2 + cosx/2-1 ) = (secx/2 - 1) ?
  
  
• ^tamago^

  2 Nov 07, 12:44

  Originally posted by Isis:

  Can (tanx/2 sinx/2 + cosx/2-1 ) = (secx/2 - 1) ?

  Let x/2 be A.
  
  LHS
  = tan A sin A + cos A - 1
  =/= sec A - 1
  =/= RHS
  
  
• eagle

  2 Nov 07, 18:39

  Originally posted by ^tamago^:

  Let x/2 be A.
  
  LHS
  = tan A sin A + cos A - 1
  =/= sec A - 1
  =/= RHS
  
  

  tan A sin A + cos A -1
  = (sin A )^2 / cos A + cos A -1
  = { (sin A )^2 + (cos A )^2 } / cos A - 1
  = 1 / cos A - 1
  = sec A - 1
• ^tamago^

  2 Nov 07, 18:54

  *dies*
• Isis

  2 Nov 07, 18:59

  Thanks !!
• eagle

  2 Nov 07, 19:15

  Originally posted by ^tamago^:

  *dies*

  don't worry
  
  It's eagle that's why