Posted by Proving Identities Question (Trig.) on Friday, July 18, 2008 at 12:04pm.
Prove the following identities:
a) (cosec θ + cotθ)(cosecθ  cotθ) = cotθtanθ
b) 2/(1 + sinθ) + 1/(1 sinθ) = (3sec^2)θ  tanθcosecθ
I basically just have to prove Left HandSide = Right Hand Side

math  drwls, Friday, July 18, 2008 at 1:06pm
(a) You should immediately recognize that the right side equals 1. If you don't, then review the relationship of tan and cot.
Multiply out the two factors on the left and you get
csc^2 θ  cot^2 θ) = 1
Rewrite the left side as
1/ sin^2  cos^2/sin^2 = 1
which is the same as
(1  cos^2)/sin^2 = 1
1 = 1
For (b), I suggest first rewriting the left side with a common denominator. Also recognize that tan*csc on the right equals sec = 1/cos

math  Anonymous, Saturday, July 19, 2008 at 10:42am
Thanks drwls that really helped !
:)
Answer This Question
Related Questions
 turnford  prove the following 2 cosec 2θ cos2θ = cotθ  tanθ...
 turnford  prove the following 2 cosec 2θ cos2θ = cotθ  tanθ...
 Math  Calculus  The identity below is significant because it relates 3 ...
 math trigono  1. If tanθ = –√3 , what is the value of cot ? 2. ...
 Math Question  Given tan θ = 8/5 and sin θ < 0, find sin θ, ...
 Trig  Given that csc θ = 4 and tan θ > 0, find the exact value of...
 Trigonometry  Could someone please help me with the following q's I'm having ...
 Precalc/Trig  Sorry there are quite a few problems, but I just need to know if ...
 Math Question  Find the values of the six trigonometric functions of an angle ...
 trig  The terminal side of θ lies on a given line in the specified ...
More Related Questions